Can't host private (XMPP) server ? Jabber Vassal Crash

OS: Windows 10
VASSAL: 3.2.17
Java: 1.8.0_201
Module: Any (tried custom ones and VASL)

2019-03-11 17:34:47,749 [0-main] INFO  VASSAL.launch.StartUp - Starting
2019-03-11 17:34:47,749 [0-main] INFO  VASSAL.launch.StartUp - OS Windows 10 10.0
2019-03-11 17:34:47,749 [0-main] INFO  VASSAL.launch.StartUp - Java version 1.8.0_201
2019-03-11 17:34:47,749 [0-main] INFO  VASSAL.launch.StartUp - VASSAL version 3.2.17
2019-03-11 17:34:47,839 [0-AWT-EventQueue-0] INFO  VASSAL.launch.ModuleManager - Manager
2019-03-11 17:34:51,403 [0-SwingWorker-pool-164441608-thread-1] INFO  VASSAL.launch.AbstractLaunchAction - Loading module file D:\Documents\Vassal\Radar
2019-03-11 17:34:51,423 [0-SwingWorker-pool-164441608-thread-1] INFO  VASSAL.launch.TilingHandler - No images to tile.
2019-03-11 17:34:51,423 [0-SwingWorker-pool-164441608-thread-1] INFO  VASSAL.launch.AbstractLaunchAction - Loading module Radar
2019-03-11 17:34:51,429 [0-SwingWorker-pool-164441608-thread-1] INFO  VASSAL.tools.io.ProcessLauncher - launching C:\Program Files\Java\jre1.8.0_201\bin\java -Xms256M -Xmx512M -DVASSAL.id=1 -DVASSAL.port=51566 -Duser.home=C:\Users\[redacted]-Duser.dir=C:\Program Files\VASSAL-3.2.17 -cp lib\Vengine.jar VASSAL.launch.Player --load -- D:\Documents\Vassal\Radar
2019-03-11 17:34:52,027 [1-main] INFO  VASSAL.launch.StartUp - Starting
2019-03-11 17:34:52,028 [1-main] INFO  VASSAL.launch.StartUp - OS Windows 10 10.0
2019-03-11 17:34:52,028 [1-main] INFO  VASSAL.launch.StartUp - Java version 1.8.0_201
2019-03-11 17:34:52,028 [1-main] INFO  VASSAL.launch.StartUp - VASSAL version 3.2.17
2019-03-11 17:34:52,028 [1-main] INFO  VASSAL.launch.Launcher - Player
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - VASSAL images folder found at jar:file:/C:/Program%20Files/VASSAL-3.2.17/lib/Vengine.jar!/images/
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family network-server created for network-server.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family go-down created for go-down.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family network-idle created for network-idle.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family VASSAL created for VASSAL.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family calculator created for calculator.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family go-up created for go-up.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family VASSAL-jabber created for VASSAL-jabber.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family jabber created for jabber.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family bug created for bug.png
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family yes created for yes.svg
2019-03-11 17:34:53,130 [1-IconFactory-preload] INFO  VASSAL.tools.icon.IconFactory - Icon family no created for no.svg
2019-03-11 17:34:53,589 [1-AWT-EventQueue-0] WARN  VASSAL.launch.BasicModule - Radar version 0.0
2019-03-11 17:34:56,769 [1-AWT-EventQueue-0] ERROR VASSAL.chat.jabber.JabberClientFactory - 
2019-03-11 17:34:56,893 [1-AWT-EventQueue-0] ERROR VASSAL.tools.ErrorDialog - 
java.lang.IllegalArgumentException: Field not found for the specified variable name.
	at org.jivesoftware.smackx.Form.setAnswer(Form.java:253) ~[smackx.jar:na]
	at VASSAL.chat.jabber.JabberRoom.join(JabberRoom.java:143) ~[Vengine.jar:na]
	at VASSAL.chat.jabber.JabberClient.setRoom(JabberClient.java:456) ~[Vengine.jar:na]
	at VASSAL.chat.jabber.JabberClient.setConnected(JabberClient.java:335) ~[Vengine.jar:na]
	at VASSAL.chat.HybridClient.setConnected(HybridClient.java:82) ~[Vengine.jar:na]
	at VASSAL.chat.DynamicClient.access$001(DynamicClient.java:39) ~[Vengine.jar:na]
	at VASSAL.chat.DynamicClient$1.done(DynamicClient.java:94) ~[Vengine.jar:na]
	at org.jdesktop.swingworker.SwingWorker$5.run(Unknown Source) ~[swing-worker-1.2.jar:na]
	at org.jdesktop.swingworker.SwingWorker$DoSubmitAccumulativeRunnable.run(Unknown Source) ~[swing-worker-1.2.jar:na]
	at org.jdesktop.swingworker.AccumulativeRunnable.run(Unknown Source) ~[swing-worker-1.2.jar:na]
	at org.jdesktop.swingworker.SwingWorker$DoSubmitAccumulativeRunnable.actionPerformed(Unknown Source) ~[swing-worker-1.2.jar:na]
	at javax.swing.Timer.fireActionPerformed(Unknown Source) ~[na:1.8.0_201]
	at javax.swing.Timer$DoPostEvent.run(Unknown Source) ~[na:1.8.0_201]
	at java.awt.event.InvocationEvent.dispatch(Unknown Source) ~[na:1.8.0_201]
	at java.awt.EventQueue.dispatchEventImpl(Unknown Source) ~[na:1.8.0_201]
	at java.awt.EventQueue.access$500(Unknown Source) ~[na:1.8.0_201]
	at java.awt.EventQueue$3.run(Unknown Source) ~[na:1.8.0_201]
	at java.awt.EventQueue$3.run(Unknown Source) ~[na:1.8.0_201]
	at java.security.AccessController.doPrivileged(Native Method) ~[na:1.8.0_201]
	at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source) ~[na:1.8.0_201]
	at java.awt.EventQueue.dispatchEvent(Unknown Source) ~[na:1.8.0_201]
	at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source) [na:1.8.0_201]
	at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source) [na:1.8.0_201]
	at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source) [na:1.8.0_201]
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source) [na:1.8.0_201]
	at java.awt.EventDispatchThread.pumpEvents(Unknown Source) [na:1.8.0_201]
	at java.awt.EventDispatchThread.run(Unknown Source) [na:1.8.0_201]

Alright, so I wanted to use the Jabber server feature to host a private server.
I organize online megagames, which involves lots of players and occur on multiple weeks. No software like Vassal provide the necessary toolset to host this type of events online this smoothly. I heard the main legacy server often crashes and I didn’t want to risk it. So I tried setting up a Prosody server on my VPS to try and host on a private Jabber. I had this error happen everytime I pressed “Look for a game online” with the server preferences correctly set up.

I tried changing settings on my Prosody XMPP server, and even borrowing other ones to test if it came from my setup. Same crash happening.

No idea how to fix this.
Although, if anyone knows how we could safely host the same game for multiple days, it would be nice. Now that I know about the power of Vassal I can’t come back to anything else.