Here's my crash log to cross reference. When I enter the end portal the client crashes. I am able to reload the file and I end up a few blocks away from entering the portal.

When I bypass the end portal entirely I am able to get to the end without issues. (/execute in the_end run tp player locationcoords)

crash-2020-09-25_13.41.08-server.txt

something appears to be blocking it. bad world gen?

yeah, must be. I found a workaround by using the TP command and then setting up waypoints so I didn't need to use the portal. Doesn't appear to be happening in other saves/worlds... so probably a non repeatable fluke. This can probably just be closed.