Since ya' don't wanna mangle the freezer lid, ( for possible future conversion), I would mount another catch of some sort, ( or another bottle opener), and stretch a DECENT bungee cord between the two,( across the lid, aft of the taps).
It's "outboard" of the hinges enough, that you should have a decent "arm" to fight against the tendency for the lid to fall open.
The factory hinges have a "spring assist open", your other option would be some "spring assist closed" hinges for the lid to the collar attachment point.
I think they are called "gate hinges"..........That's if the freezer lid can stand the stress of those particular hinge springs.
Lookin' like a bungee cord to me!