[joegr]

...The trunk will not open from the dash mounted button either, correct? ...

That's not at all my understanding from the OP.
.

...but the release on the dash and key fob both work. ...

I'm thinking two separate problems.
1. Probably a wiring issue with where the wiring bundle flexes at the trunk lid hinge.
2. Possibly the solenoid on the fuel door release has failed, or the wiring going to it.

Both possibilities are very easy to troubleshoot and narrow down with a multi-meter.

 

[joegr]

Yes, but he wouldn't be doing that every single time he needed gas!

Well, I would get it fixed pretty quickly, but others may be willing to put up with more for longer...

 

[joegr]

...Your last sentence says the dash button for the gas door has never worked. I don't know how this is possible as it's the only way to get that door open to put gas in your car...

There is a mechanical pull cord in the trunk to manually release the fuel door if the electrical release is not working.