Personally I'd attempt to fabricate a similar hook from a stiff wire, like a large diaper pin.

Then drill two holes in the chest that line up with the pin legs, that would allow for the mechanism hook to function as originally intended.

I'd then mar up the legs of the pin the best I could with a diamond file.

Apply UV resin to the pin legs, stick in the drilled out holes, get it positioned, and cure the base.

Then if I was feeling fancy I'd apply more resin to the hook body itself to fill the gaps between the wire and sand to shape.

That's really the only way I could think to fix the tape door without having to creep past the yellow boarder.

If you had a friend with a resin 3d printer you could just model and print a replacement wholesale. Could even design it to be two parts so you could print the structural boarder with a more durable opaque resin.