Unfortunately, I think you have successfully identified all the possible approaches and their drawbacks. If you are at a smaller company, perhaps you can ticket directly in F and submit a receipt for Y as reimbursement (after clearing this with your employer) -- this is what I did in a past job. But this is unlikely to work in a large or bureaucratic company. Upgrading for the "fee" cost will never earn PQD/RDM, and upgrading directly with United will almost always price to the public First fare and not your corporate rate. By the time you want an agent to ignore the agency takeover issue, understand GG BUYUP, and ticket you a private fare you're asking way too much for luck of the draw.