There were an overwhelming number of red flags that your account was a sockpuppet of a suspended user, including multiple critical internal indicators (which initially raised the issue), typing style, post types, and active times. In addition to that, we were already on high alert for such signs matching certain criteria, as this particular suspended user has created several accounts to continue posting despite their suspension. The creation date on your main-site account had obvious alignment with the day their other most recent account was destroyed, and followed these same patterns.
The standard advice to moderators on SE is to destroy the accounts of users who have been suspended if they continue to post to the site. A remarkably high number of indicators suggested this was the case. While it would genuinely astonish me to find an account with such a plethora of indicators that wasn't a sockpuppet, I can't deny that it's possible, and if it's happened here, all I can say is that I'm sincerely sorry.
I hope I've at minimum cleared up why such a thing could happen, and why I wasn't really worried about this being possible when I went to hit the destroy button.
Your best bet for re-associating posts from your old account is likely going to be to contact a Community Manager using the Contact Us link at the bottom of the page; this is not something we (moderators) can do.