Start small, things of no consequence, and test. Reading the above linked wiki, it seems like it will be current insulating not conductive, yet thermally conductive, so suitable for the job.
20lbs? If it works start selling film canisters full, or some such similar.
And a third if I recall was using a theoretically better ‘silicone’ replacement too. Cant think of that thread… but it was recent
Edit: Here we go Thermal Test: Fujik vs RTV Silicone vs Insulcast
We might have some BLF unobtanium…