unyquity
Slippery elm *will* grow skin on decubitus ulcers - mixed with aloe gel, it'll happen even faster!
Take Slippery elm powder and mix it with (top quality) aloe gel until you have the consistency of very soft 'play dough'...then pack that into/onto the bedsores no thicker than 1/4
inch. Even at 1/4" thick it will take a while for it to dry.
If possible, use a hair dryer 'on low' to help dry the 'poultices' (at least a foot away as to not burn his skin). Once dry, this mixture may crumble a bit on the edges, but it will definitely 'stay put'...and that's exactly what you want.
In a day or two you can add another layer (usually thinner and moister to get it to 'stick'). Soon you will see (as you look beneath the edges) that the skin has started to regrow (or as already regrown).
The slippery elm/aloe will either absorb into the skin or crumble away revealing the new skin.
Also, a slippery elm porridge with aloe mixed in would benefit this process immensely...as would strong doses of echinacea (because echinacea is VERY beneficial for rebuilding/restoring the skin, although most don't know that).
How WONDERFUL that your knowledge has reached the level you're able to help others...especially your dad!
Blessings,
Uny