I didn't have enough wax to actually boil the sheath in the wax so I went to plan B. I double boiled 5 bees wax tea lights in a metal cup and borrowed my wifes heat gun (she's into crafts like I'm into survival) to heat the leather up. I applied the liquid wax to the leather using a clean tooth brush and used the heat gun to keep liquifying the coats over and over again scrubbing the wax into the leather. When enough dripped off that there wasn't much of a coating, I'd apply another coat. I think I spent nearly an hour painting, heating, and scrubbing.

Then I put the knife in, wrapped the whole thing in foil (I got it a little too hot to touch) and began to mold it until it cooled. When I unwrapped it there was a lot of wax cooled on so I used the heat gun and a wad of paper towel to wipe off the excess and get it out of the stitching as best as I could (if you look close there's still wax solidly inside the rivet). Then I wrapped it in a dish towel (too hot again) and moulded it until cool. This absorbed any remaining wax and wiped off anything which dried on the surface. Then I buffed it out with a microfiber cloth to give it a little shine.

Not actually applying the wax to the inside is likely why I didn't get it super hard but I didn't want to make a huge mess on my first try or even ruin it.