Yup, that should have gotten the form out of the cache.
I'm sorry - I really can't think of much else. In case it is any help - my basic troubleshooting involves first narrowing down if it is the user or the machine - have the user log into a machine where things work - does s/he still have the issue? Log into the user's machine - still have the issue?
You'd mentioned deleting and recreating the user's profile cleared this up - but for how long?