I had a similar problem, with a much gnarlier insurer than Allstate, and the answer turned out to be to contact my own insurer (Progressive) and ask to have the claim subrogated --- Progressive paid for my damages, and then went after the liable insurer themselves.
That works only when you have comprehensive coverage, but then it works really well, also because you'll avail yourself of the rental reimbursement that you have on your policy. But the OP wrote he drove an old beater car and most likely carried only liability coverage. They'll defend against claims from other parties then but won't assist you with your own claims.
