Looks like your tt has a frig roof vent. Skip the drilling completely. Up through the wire mesh, out under the vent cover. Remove on roof vent screw. Make a simple met bracket for that location. Put the screw back in. Should attached to a good reinforced location.
No new holes. No new decor location to maintain.
2012 Jayco X23B
2020 Ram Laramie 3500 SRW Air ride 50Gal fuel tank.
2007 Dodge Dakota Quad Cab (retired from towing)
Equal-I-zer 4-Point Sway Control