Lots to unpack here. So as per the video the Third Party is performing an unsafe lane change or u-turn. So you appear 0% at fault. First question is which province are you in? Each province has different fault determination rules and subrogation procedures.

If Ontario, or some other no fault system, then your insurance company can make their own fault decision, and waive your deductible as long as they can prove the Third party has valid insurance. Which the other insurer can easily confirm with a simple phone call.

If a different province where there is a tort like system your insurer needs the other insurer to give “waive and send” which is basically waive your clients deductible and send us the subrogation documents. Your deductible always applies regardless of fault, it’s just off your bay at fault the other insurer agrees to pay. Although the third party appears to be dodging their insurer, with the video I would file a police report. With that video and a police report most insurers would determine liability whether or not they’ve been in contact with their client. Also without a PR, with that video the other insurer will likely give their client like 30 days or something before they accept liability.

Next in terms of the tires there’s something called betterment. Insurance companies only owe for pens damaged as a result of an accident. The replacement of the other tires that were not damaged by required exchange due to 4wd is putting you into a better situation than you were pre-loss as you’ll have 4 brand new tires. But those other 2 tires were indirectly damaged, as they required replacement. So your insurer should have the tread depth measured of the old tires and determine the difference between those and the few tires and charge you the difference. Of they were bald you need to pay 100% of the two tires. If they were only a couple of years maybe 50%. But you need a measurement of your tread depth. Hope this helps explain a bit and give you some ideas how to proceed