I figured out my issue...
MongoDB user I was using had a readWrite role, but I guess it needs the dbAdmin role as well. When I tried creating a new user in the nodebb admin area, then it would make things go wonky without the dbAdmin role and result in invalid csrf tokens.
Related Github issues:
PostMidnight created this issue in NodeBB/NodeBB
djensen47 created this issue in NodeBB/NodeBB
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