Just wanted to reply. Think I got it solved myself. A few more hours of mucking around in server's newer firewall and it magically turned on about 20 minutes ago.

Added the dynamic ports, SQL Server exe and SQL Browser exe to the firewall. And also adjusted a few settings in the TCP/IP settings of the SQL Instance. I don't think the latter did much, but as it is working.. I am so not changing them back at this point. 😀