When did Henry become Spider-Man? I mean, how else would he climb a mountain in those shoes? How else is he not getting pulled off the damn cliff by the weight of Benny? And he has horrible dress sense, just like 1970s Spider-Man. (John Romita was a fine artist, but I am unconvinced Peter Parker is a "fringed leather vest" kind of guy.)
I'm not even sure you can have a mystery on a mountaintop anyway. I mean, how many suspects can you possibly have? "There's two climbers and one sherpa and a diamond smuggler. Now let's figure out who's been smuggling these diamonds!" It's ludicrous. This is probably "The Commercial Hiking Trail Mystery" and they just decided to sexy it up. Still doesn't explain Henry's penny loafers.