My guess is the PO lost the radiator and it overheated. That's about the right mileage. And you wouldn't replace both head gaskets if just one side was leaking unless you had reason to believe the cause was common and bank two failure was imminent. It was done at a dealer, so you should have a reasonable expectation that it was done correctly and using Toyota OE parts.
I'd run a Blackstone sample on the next oil change and make sure there's nothing naughty going on post-repair and then again for the next several changes.
As far as the exhaust studs, my 2013 came out of Walnut Creek, CA and I had zero corrosion issues when I removed the header for a prophylactic starter replacement. I bought extra studs and nuts for the job. I used new nuts just because I had them but the studs were perfect.
As far as the shock, those are wear items. If it's weeping it's likely of age to not be damping properly. Replace them.
I'd run a Blackstone sample on the next oil change and make sure there's nothing naughty going on post-repair and then again for the next several changes.
As far as the exhaust studs, my 2013 came out of Walnut Creek, CA and I had zero corrosion issues when I removed the header for a prophylactic starter replacement. I bought extra studs and nuts for the job. I used new nuts just because I had them but the studs were perfect.
As far as the shock, those are wear items. If it's weeping it's likely of age to not be damping properly. Replace them.