Update: VLTOR confirmed the upper is out of spec and is shipping me a new one today. Can't say enough about their responsiveness. They had me on the phone giving me a RMA within an hour of me sending them an email complaining of fit. Then today, they got the upper from me and called me back in under 3 hours from receipt to confirm it being out of spec and that they'll be shipping me a new one today.
Now... just have to wait for Ident to get my lower engraved and back to me so I can test fit the replacement.