I might be able to help on this one — I did some of the early work on Exposure Notification tech and was somewhat involved with discussions between Apple/Google/a few governments.
We partially answer some of your questions here: https://arxiv.org/abs/2306.00873. I'm also happy to try to answer any related questions (some parts are closer to informed guesses and didn't make it into the academic paper).
Congrats on launching the org. Would developing plans to avoid gradual disempowerment be in scope for your research?