Seems to me Prime Trust went scorched earth after the lost keys fiasco. Hired interim management to claim plausible deniability and jumped ship to the new “trusted” Fortress.
That’s my theory. 🧐 
Discussion
I believe Swan is using Fortress as one of their 2 custodians. I know Swan is always pushing for self custody but I believe they offer retirement or IRA accounts for bitcoin. Those I would assume would need to remain in the custody of the 2 companies they use. Wonder if they are looking into these discoveries between Prime Trust and Fortress.