Would have liked to see pictures of the rear main seal area... Usually they leak because the oil gets baked and forms a hard ring on the crankshaft and allows it to seep by the seal (highly recommend lightly scrubbing the crankshaft before you reinstall the new seal). The other thing, that is a bit more rare but I just dealt with it on a 2019 a while back was that the oil galley plug above the rear main seal will seep oil and look like a traditional rear main seal plate leak. There's no "official" fix for this beyond a short block, but it can be fixed with some creative thinking if you're willing to risk it.
As for the timing cover leak, again would have been nice to see pictures (does this dealership not do that?), but you might still have an actual timing cover leak. Though I would be shocked to find one pissing a quart a day, if I noticed the cover was actively dripping like that, it would be a red flag for sure. I have seen a few Toyota Oil Pressure Switches/Sensors leaking badly, something about the crimp seal or something, they'll literally pour out of the connector housing. We had a rash of them years ago, a bad batch from the supplier I guess? But haven't seen it as often in the last two-three years.
Judging roughly by the vehicle you own and the estimates I am going to guess you have an XREAS system. Generally speaking, if the vehicle is high mileage and you're showing signs of a decent leak on the shock, it's recommended by Toyota to replace the companion shock, center dampener, and associated lines. Also standard practice is to replace shocks in axle pairs, which because it's XREAS, ends up meaning all 4 shocks, center dampeners, and lines. So that's not out of the ordinary, though pictures of the leak would have been nice to see as if it wasn't too bad a leak and you have relatively low mileage you could probably try getting away with just 1 shock.
I can't say they weren't trying to screw you, I have heard some horror stories both on the forum and from others in the industry about dealerships on the East Coast and Southern Regions (not just Toyota ones). But depending on the age/mileage/condition of your vehicle and the actual condition of the leaks when they recommended it, it's possible that whoever looked at the vehicle just didn't catch the signs of a leaking oil pressure sender (again, it's uncommon... but I have seen it happen a few times) and just recommended what they are used to seeing. That being said, they are a business; what would have been truly sleazy is to charge you $4k for a timing cover reseal and then make you pay for the oil sender replacement even though it'd be their incorrect diagnosis on your active oil leak.