Alright, it's fixed. I think the ISP guy failed to mention that I had to manually reboot the modem to apply the new IP. In frustration I decided to just turn it off and on again and it seems to be now allowing me to connect after he applied the new IP a few hours ago.
That was the most useless, baffling, & frustrating situation I've run through. I guess It was a modem reset, or Nitrado actually fixed their servers in the New York area. Unsure what it is, I'm now going to have fun with this 'plausible' new IP of mine, as well as being able to play again. Let's take advantage of it.
You can mark this now as solved. Rejoice, for you shall not hear about this again! *knocks on wood*