My car ended up being in the shop for about a month and a half. I went through my insurance initially for the car rental, for which I had 30 days of coverage. Once that was up, the other insurance (All-State), which accepted 100% fault, covered the rest of the time but they had a super low daily rate so I ended up in a Kia Rio for 2 weeks.
As for diminished value, unfortunately as far as I know, based on the research I did for my own rear-ender, since the other driver has the same insurance company, you won’t be able to get diminished value compensation.
Situations like this sucks and I feel your pain. Good thing you seem to be safe and hopefully your car will be brought back 100%. Good luck!