It seems that the family sold a 250 Testa Rossa for the 962, which was previously owned by Vern Schuppan.

Unfortunately the pics aren't in the article anymore, but its a great read.
https://www.roadandtrack.com/new-cars/car-comparison-tests/a25128/legends-the-porsche-962-and-918-face-off-at-indy/

No clue how they ended up with both Jags. A search shows one on the market a few years back, not sure how they sourced the other one.