Now that's a new one. Never heard of anyone want to fix a dent and maintain the patina. Had to think about this one. hard too see the extent of the dent on those pics. Hard to know what is in your mind regarding what "fix" would be. Hard to know how much affect on patina is too much for you. Assuming you do not want to recreate patina with paint, here's my take.
1. Going in with metal or wooden pushers will take out deep parts. Once you start pushing and knocking to hard, you leave outward dents. All in all with this method it will never be smooth. If smooth is what you want instead of mostly smooth, this method won't work.
2. if no 1. is not going to give a result you are after, all the other methods leave holes or surfaces to be patched, bondo'ed, filled, ground, sanded, painted.
3. I had a 60-66 tail gate with no access. I cut out the dent, reshaped the dent and welded it back on. Grind bondo paint. (wasn't that a TV car show?)
4. The only "method" that does not require "working" the metal is..........attach a schrader valve to her and crank in 100 psi.
5. The best interim idea is what TandM suggests. Leave it alone and drive around with it for a week or two to see if it bugs you or ain't so bad.
