$400k Rv Likely Totalled By Shop.

Location: Oregon Hello wizards of reddit, my grandparents owned a 400k mobile home that needed body work done. Drop it off at an RV shop and pay a few thousand in repairs. A year and a half later it was fixed but the owner reported new problems with the RV that were not there when we initially dropped it off. 28,000 dollars for several repairs and 5 years later the shop owner and his agents go silent. We reached out repeatedly and heard nothing back. Don't even know the location of the RV. The RV has full coverage by progressive and has been paid since we got the rv. We reached out to the insurance company to find the RV. Upon doing some digging the insurance company located the RV and sent agents to the scene. They found the RV, took photos of interior and exterior. Nothing had been done and the condition inside was worsening. A year later still havent heard anything from the shop owner, recently found the RV in a random field/junkyard with a tarp over it. Went inside to take photos and the condition had severely worsened. After talking to a RV specialist he said it was very likely totalled in the present condition. Filed a new claim with new photos with progressive. They tell us the shop owner claims he was not paid. We have receipts and banks statements proving our payment at every step. Progressive agents are still processing our claim, but an agent told us it was unlikely our claim is approved under full coverage (LOL). Told us to take legal action against the shop. Doing research we found that the shop owner is living in a mobile home. Very unlikely he has anything worth more than a few thousand. Progressive told us we've done everything possible correctly... but it seems like we're about to be screwed. Any advice helps, thanks for the read.