Of course it's a scam --- and I think you already know that. For starters, it was a "cold call". Secondly, no timeshare on the planet (including yours) is worth $49k in the resale market.
'Tis the season for these types of scammers. With maintenance fee bills now right around the corner, hungry parasites like these crawl out of their little holes in the ground around this time each year, prepared to take advantage of gullible and / or desperate people.
Having presented those enticing big numbers to put big dollar signs in your eyes and a big smile on your face, their next play will be a sudden requirement for you to have to pay a bogus "escrow fee" or some other such "refundable later" nonsense charge. If you pony up the money, shortly thereafter you will hear a faint POOF! sound as they (along with your money) promptly disappear into thin air --- neither to be heard from ever again nor located.
They have absolutely no interest in your timeshare --- and never did. They are only interested in taking money from anyone who will fall for their "pitch". When enough people report having been scammed and the "company" name gets sufficient negative exposure, they simply change their "company" name and start running their scam all over again under a new name. The sad, unfortunate reality is that parasites like these know that "a fool and his money are soon parted" and they are happy to take full advantage of that old saying.
KC