I had a customer case for this exact issue.
The problem resolution was a bit surprising.
This performance counter did not exist on that target machines.
If you see this same issue I would suggest rdping to the node/sever you expected this performance counter to be on -> open Performance monitor -> click the "+" -> there should be a category AD FS.
Under this category should be the "Username Token Validations" performance counter.
If you do not see it on your machine then it does not exist and SW cannot monitor it.
If you see this issue and DO find that performance counter on your machine please open up a support case.
Otherwise you might just want to disable that component on your monitor.