Outbound sync of attributes not working

I'm trying to update a couple of attributes in a SQL table I use.
Importing data from a simple HR table works fine (emplid, firstname, lastname, address) using a declarative import sync rule. After running the FIM MA the records show up in FIM portal. I then update the address which I can see being updated in the MV.

Now I want to flow that updated address back into the SQL table. I have setup an outbound sync rule to update the SQL table using 2 attributes, emplid and address. Emplid is also used in the relationship criteria and is set as initial flow only). However when I run the FIM and SQL MA's, the outbound sync rule shows "not applied" for the attributes. It shows the old address in "initial value" but final value is empty.

If I remove the declarative rule and create a classic attribute flow by just exporting the "address" attribute it works.