AFAIK they would get the info “which user said what”. The source would be what ever instance you are from tho, not your own ip. So the owner of a instance knows as much as everyone else.

I am not sure as well, but maybe they meant “maybe an early and public disclosure increases the urgency of the fix for the developers”?

I think your estimations are reasonable, but some further information: it is not just a normal screen (with normal picel density) at a bigger size, but the pixels are rather far apart. So I would assume that this reduces the cost.