Would a beam rack work? I've heard you might need to change the seat post if its CF, but it might help.

Tucson commuter here. You should be OK with wet wipes; the only potential issue may be getting your hair un-sweaty. When I commute in summer, I have to remember to bring a hat or kerchief for my head on the days when I can't shower after arrival. Also, wait until your core has cooled down before putting on fresh clothes.

I shower before I leave and just change clothes at work.

You don't stink if you're already clean when you sweat.

I bought four beam racks before giving up on the concept. 3 out of 4 wouldn't clear my legs when pedaling and the fourth didn't have strong enough side frames to keep a pannier out of the spokes.

Quick-release skewer mounts for the bottom are available, plus brake-bridge center stays and seat-clamp mounts for conventional stays at the top.

It gets pretty hot here in the summertime. When I get to work, I go to the mens room and take a duck bath. Strip down to the waist and just wet and use up the paper towels. Soak your head and then dry off using the paper towels. Then use your deoderant and any body spray you might use and change into work clothes. Worked everytime.
Ernest

I do manual labor in a warehouse, so if I smell like poo, it really does not matter.