Looking for any advice on what I should do with a car repair.

I took in a tire with a bubble on the sidewall and got the tire replaced. I also got an alignment done and now I have two mechanics (dealer and independent) who say they could not get the alignment in (results of the first attempt posted below).

I got an initial set of repairs done to include lower control arm, eccentric bolt, eccentric bolt plate, and locking nut. Apparently it helped but did not fix the issue (asking for the new results but I haven't gotten them yet).

Now the mechanic wants to replace the right rear knuckle, wheel bearing, and right rear upper control arm, bumping up the cost to ~$2400. I have not been told of any visible damage to any components (I even took it to a third mechanic who didn't do alignments but he couldn't find any visible damage) and I didn't notice any issues while driving. Is this the right troubleshooting path, what questions should I be asking the mechanic to show me, or should I be wary?

Thank you for any help anyone can provide in advance.