I am seeing this in most of our workflows that have the Query User Profile action
Error querying user profile. UserProfileDBCache_WCFLogging :: ProfileDBCacheServiceClient.GetUserData threw exceptionSystem.TimeoutException
After this error the WF fails.
For the workflows that progress past the Query User Profile action, it looks like the action is never evaluated. We use this action to determine the next approver in the approval hierarchy and since its not working we have approvals going as far as the CEO.