I don't know why Retina was banned, or if I did at one point I have forgotten.
There were a lot of anomalies that seemed to suggest S. Therapist was indeed an alt of Mday. Hilariousandco picked it out first, and he has a bit of insight (behind the scenes) that the rest of us don't.
By the time the Retina account was created, the forum had already run Mday and S. Therapist through the wringer, so I would imagine that if Mday did create another alt he would have taken precautions to ensure that accounts anonymity.
From my personal perspective I can't say that I've seen conclusive evidence that Mday and S. Therapist are alts, but I've seen enough BS and squirming from both accounts to say that's A strong suspicion of mine (and I'm not alone.)
I will also say that I haven't seen enough to be convicted Retina is indeed an alt. But, I am inclined to trust Hilarious, and I don't believe a single word Mday writes.
When the recovery team was in the process of recovering my account they checked my current IP (since they asked for it this means they have checked all the IP history they had in the system connected with mdayonliner), they even asked for my located city, country kind of things too.
That's a strawman argument and it's completely meaningless. Alts aren't against the forum rules, so as long as the banned Retina account wasn't connected to the same IP, the recovery team won't do anything about any other alts. Who's to say that recovery team did check to see if you've accessed the forum from the same IP as Retina? Did they?