Thats a lot of bad/sad news in one post........Im sorry in so many ways for you.
IIRC the 'criteria' about Ruger working on modified firearms is on their website, but still, the CSR on the phone gave you the wrong information. I guess I would want to go farther up the chain of command (when I could stay cool and calm) and talk to a supervisor, explaining the whole thing and 'asking' what they think a good resolution might be. I wouldnt count on the fix, but who knows, and maybe they would at least do something about the shipping charges you likely paid for.
Keep reminding yourself that you catch more flies with honey than you do with vinegar.
FWIW, the old Colt's Frontier Scout wasnt any safer than the Bearcat, its good gun handling that needs to be taught more than depending upon 'safety features'.