I don't know that a temporary facility is going to work when you are talking about that many pools, that deep etc. I could be wrong, I just don't the area going with a stopgap.
It runs through 2027, 30 year lease. Word was that they would be willing to let them out early if they could get the new FBI building for the site.
We're talking about two different things. I'm saying a temp facility for the Opening/Closing as well as track events, that's what Chicago was supposed to be IIRC. That said, I think it's somewhat likely they'd build temp facilties for aquatics as there would be little use for them after the games, they'd just need seating and media capabilities.
Even, if the Skins couldn't get out of their lease, maybe the new stadium is just a white elephant for a few years.