I tried running /map radiusrender minecraft:overworld 2000 10000 300 as a vanished player in spectator and got no feedback on the command. I had the right permissions and was unsure if it would start since I am vanished so I though "Can't hurt to run that command a second time from console to be sure."
Nope. As soon as I ran it from console it crashed. I am not sure if the issue is solely on squaremap or has to do with other plugins or something else but I wanted to provide the crash-log here regardless.

crash report: https://mclo.gs/7WRuwDi

Sadly a crash report isn't really useful here, need the server log to say anything.

Here is the begging and end of the log from that day.
It seems that DiscordSRV was the culprit and not squaremap.
https://mclo.gs/pjZyLYs#L559

Here is the begging and end of the log from that day. It seems that DiscordSRV was the culprit and not squaremap. mclo.gs/pjZyLYs#L559

Thanks for the update, going to close this now then