It may very well be a scam, but we need more info:
Buyer's name.
Escrow company's name.
Does the buyer claim to be hearing impaired?
Is the offer more than it's worth on the resale market?
Generally this is what happens:
1) They charge you bogus upfront fees and then steal the fees.
2) They send you a fake check for more than the agreed upon price and ask you to send the difference to their "broker." Their check bounces and you lose the money you sent.
This would be my response. "I want to use MY reputable timeshare title company, LT Transfers, and I will pay all the costs to use them."