Unresolve decision based on created by

I need to add an assignment when the unresolved action is taken that uses a decision to work out who is taking the un resolve action. if end user the assigns to a group if not end user then add assignment to the Lastupdatedby record.

What happens if the Analyst unresolves this correct assigns to the lastupdated by which is was the analyst as they used the un resolve action, if the end user uses the unresolve it sets the assignment to the end user and not the helpdesk group.]

To me this means the last updated by on the unresolve is not being returned in the decision so nothing equals user type End User.

As far as I can see last updated by is populated just the decision is not seeing it, Any ideas?

Thanks, Gareth