Generally damage caused whilst the home is still in the ownership of the seller and caused by the sellers termite company, rests with the seller.
It's too bad that the sellers were unwilling to step up. Hopefully they were advised by their Realtor to do so. You shouldnt have had to pay this cost but you probably made the most prudent business choice.
Thanks for doing 2 inspections for us, and being an all-around good guy!
Sorry this answer arrives late. Disclaimer: I am not a WDO/pest inspector nor am I a real estate agent. I will offer you some information based on my 14+ years as a home inspector and participant in many real estate transactions.
The person(s) paying for tenting/repairs likely received information that roof tile damage is inevitable and the pest inspection company will not make repairs for such. Your real estate purchase contract appears to have language that states this home will be delivered to you in pretty much the same condition it was in when made your initial offer to purchase.
Your real estate agent should be able to guide you through this mess.