I can't see how this could be related to the ESXi host nor how/why rebooting the host itself would have any bearing on the ability to assign and accept a static IP on this Debian VM. Just out of curiosity, how is your ESXi host's networking set up? Can you show either a diagram or screenshots of the networking?
Assigning the static IP is not the problem. I can ping everything just fine. it's only establshing the SSH connection and the mismatch in information between what NMAP reports and my debian machine's firewall settings.
I believe it's the ESXi host and NOT the networking because I was able to SSH into this machine before I removed the old windows server.