If the platform is too obscure with little to no reputation, it's a hard pass for me.
In any custodial platforms, a good reputation is a must since they hold our coins, not to mention that there has been huge amount of never heard before fake exchanges that scammed people which is basically why the community has been telling people to stick with reputable services to play it safe.
Adding "they're buying above value" doesn't help either... as it could be said too good to be true.
Where did you get this info btw? from a random PM perhaps?
EDIT:
Serious question, do they call themselves "hidden portal" too lol?