Maybe you did avail their promo or bonuses when you deposited that's why they require you to wager based on the amount x5 which will be the wager amount that you have to reach. I don't see any reason why you won't be able to withdraw if you didn't apply to any promo or bonuses in their platform.
All online casinos have wagering requirements. Those are usually 1x or 2x. This is the first time I see a 5x rollover requirement on deposited funds. It's got nothing to do with activating bonuses. The wagering requirements for bonus money is probably much higher (30x, 40x or more).
Looks like we have found the main issue...
Multiple accounts are not allowed in casinos and even if you and your friend were in a different room both of you were on the same IP for the casino, and from that point, even without placing bets your account gets a red flag as a user with multiple accounts.
And then both users betting the same game, which was suspicious for the casino, you send them a lot of cheating signals.
Actually, OP claims he was betting on Trustdice, but his friend was wagering on Pinnacle. They weren't using the same casino. Still, the game provider can see two bets coming from the same household/IP on the same round betting on opposite results. In that case, both bets should be voided. Maybe the two friends were trying to trick the casinos and provider and got bitten in the ass instead. I don't know.
@TanyaSSS
If you believe you have a case against the casino or the game provider, take it up with a 3rd-party mediator. But I don't think you have a chance if they can prove two bets coming from the same IP, on the same game session, on opposite results.