A document has a Red X over a pencil and it shows as being in a persistent locked state via workflow logs. What does that mean? It is not checked out.
The red X over a pencil indicates that the document is checked out by someone other than yourself. Right-click on the document or open the Task menu, then go to the check in/check out menu item: there should be an item "Check out Details" that can tell you who has the item checked out.
Ok we did check this and it said that no one has the document checked out. I can also make changes to the metadata without any issue from the client. It is just that workflow can't make changes to the metadata because it says it is in a persistent locked state.
'Persistent Lock' is the internal Server term for checked out. You might try looking at the 'checked out entries' node in the Administration Console and see if it's showing up there. If not, this is probably something you'll need to talk to Support about.