Legal Question in Business Law in Illinois

First you will need to preserve the remains because destruction or impairment of evidence in the event of a lawsuit can result in defeating your claim because the seller could contend he no longer has the ability to have the cause of death determined forensically. My suggestion is that your next step would be, if the remains are capable of such examination, to take them to a licensed vet with all the packing, etc., for an opinion of cause of death, and present it to him. If he is willing to refund your money (and he should have some insurance for this purpose and your shipment should have been insured!) then you may be able to return the remains in exchange for the refund but I would suggest having an attorney here "middle" it. If he still refuses you will have to sue him for breach of contract and breach of warranty. If you sue him here and get a judgment you would have to register the judgment in Florida and pursue collection there; if he contests your right to sue him here you may have to start over there. You can also try to sue in Florida directly but of course would most likely have to hire an attorney there and travel there for any court hearings that require your "live" appearance and testifying. You may be able to sue in federal court here, or there, depending on the species. Have an attorney review the order information and confirmation, the species and the terms of the sale to determine where you can sue and whether you would be entitled to attorney fees and court costs.