Sounds like he may be ruling out a cholesteatoma or tumor with the referral. I good idea but I would take your lack of other worrisome symptoms as a good sign. And an ENT should be able to see a cholesteatoma in the office. There would only be drainage if the eardrum had been perforated.
Surgery would likely only be needed if he/she saw a tumor (surgical removal) or the retraction was chronic and causing problems (tubes).
No problems with equalising, or rather popping my ears as I'm not allowed to dive
Hard to say over the internet but could it have been wax that he removed from the canal? Sometimes, if it is stubborn, a little superficial adherent skin may come away too.
He did say skin. He assumed it was wax to begin with, but after much suction and tweezer action he said it was skin.