I was just skimming the thread and my brain read this as “Needles and flamethrowers.”
I have a drawer filled with expired Epipens. I just let them pile up.
Yes, that’s great advice, but what happens when you ask the “doctor’s office, hospital, [and] pharmacy” and they all say no? 
It’s not rhetorical. it’s what happened.
It seems your options are to buy a sharps container and put the epipens in it and mail it in or empty the epipens and bring them to the hospital.
I don’t know if you want to go this route, but you could also see if your city has a free needle exchange program (usually directed towards IV drug users) and ask them it they’ll take the Epipens.
IMO, the easiest thing to do is to unload them and bring them back to the hospital. As you mentioned (I think it was you), the fact that they’re still full of meds is causing at least some of the issues.
No way, stop driving these things around. Your earlier suggestion of tossing them in a laundry (or Gatorade or Wesson or half & half or Cobra malt liquor) bottle was perfect. Unload them first if it makes OP feel better.
It seems to me that this results in a piece of fruit loaded with epinephrine that looks tempting to a wild animal. Surely the medicine is better left in the injector, whether it’s just thrown in a trash bag or placed into a proper sharps disposal container?
Well, the OP was saying they didn’t know a safe way to separate the med from the pen and I did. Speaking only for myself I think a loaded injector is more dangerous than the alternative if free. I fully concur about use of a sharps container but that seems a non-option from some of the posts.
As to oral ingestion, I only found this which says that: “Many drugs intended for injection work equally well orally (taken by mouth). Not so with epinephrine. Given orally, epinephrine will rapidly degrade in the GI tract and is not absorbed at all.”
I realize that applies to humans, but that’s the limit to my research tonight,