If they are "investigating suspicious transactions or users", they won't reveal those details. But It's rare for some exchanges to just block funds because you refused to complete KYC verification. What they sometimes do is just let you withdraw your money while the other functions of the account remain blocked.
They don’t have to share sensitive details or information that may compromise the investigation, but I believe it’s his right to know why he can’t withdraw his money. A simple message like "we detected some suspicous activity on your account and we are investigating it" won’t hurt.
And, tbh, few exchanges / service providers will let you withdraw your balance if you refuse to pass KYC, especially if they find you hve violated their terms or tried to cheat their system.
I think it's because OP thought he should be able to withdraw amounts up to $20,000/day as Pinonex apparently claimed under KYC 1—that he passed, thus he believes he "met all the conditions" for his $295 withdrawal request.
I guess you are right and that’s, indeed, what he meant to say. But, unfortunately, we all know that this is not how things work on centralized services.