I bought mine 2011. How much did you get it and for how many years?
From what I know the gross price from the time I bought until now has not changed. Considering the 4 members I had met and whose agreement I've checked thus far.
They've only offered discounts based on the gross rate depending on how much you the buyer is willing to pay for it for Club Ultima agent to close the sale. In my observation, the tier of the discount keeps getting less lang as time goes, but the gross price had remained the same.
Also, I was informed by a friend in Cebu that Club Ultima's product offered in Cebu is a bit different from what was offered to Manila.
And yes the agent who sold it to me told me the same. Coz this part I asked and made sure.
The agent said their office will buy it back or help me sell at the current price in case I don't want it anymore.
In 2016 I called and wrote the membership office here in Manila and Alice Cabaddu (Membership Manager) also gave me the same answer as yours, that they cannot help sell my membership package because of inventories they have (which will in fact never run out for as long as all their hotels are there).
With this said, since I have nothing in writing that supported the promise and my understanding. I had accepted that this part, I have no fight.
One thing that agent told you / your understanding of what you have purchased is not true, that it's a form of investment. Can you check the Reservation Application form you signed #7.4. That is if we have the same paper.
You can only compel them to buy back your membership if you have a written agreement signed by both sides from the start.
If this doesn't work, perhaps you have other complaint that's valid and where you have a better fight?