As several have said, the best advice is to just accept, that you closed your account and then play somewhere else. But if for some reason I found myself in a situation, where I could not play on whatever site, and this was very important to me, I might ask someone close to me, who dont play poker, to open an account and let me play from it.
This is obviously a violation of the TOS, but unless you are a high stakes player, there is probably not that much scrutiny, and the risk of detection might be fairly low. Of course deposits and withdrawals will need to be done by the owner of the account, and its probably also best to not use the same IP adress, you played from before. So if I wanted to do this, I would change my internet provider first. And then also let my "helper" sign up and deposit or withdraw while using my internet.
But again... you created this situation yourself by closing your account, and its somewhat difficult to understand, why its now that important for you to play on PokerStars again? As you even say yourself, there are other sites out there, and PokerStars is not even the largest any more. So if you want to still play MTTs, then why not play them on for instance GG Poker instead?