It seems to me that there are two possibilities, and either way, Hurd should win:
1. It is possible for Hurd to work for Oracle without disclosing HP trade secrets. Then Hurd is not breaching his agreement by working for them.
2. It is not possible for Hurd to work for Oracle without disclosing HP trade secrets. Then the agreement is a de-facto non-compete agreement, and therefore unenforceable.
I admittedly don't know the details, but if he has a severance, that usually implies that he was let go. All the non-competes I've ever read were effectively voided in the event of employer termination, unless the severance amount also included a non-compete clause itself.
1. It is possible for Hurd to work for Oracle without disclosing HP trade secrets. Then Hurd is not breaching his agreement by working for them.
2. It is not possible for Hurd to work for Oracle without disclosing HP trade secrets. Then the agreement is a de-facto non-compete agreement, and therefore unenforceable.