So then I decided to talk to a network\infrastructure dude to get help (caus I is a dev).
A huff and puff and some jiggery pokery later and it turns out DNS was holding static records for the previous versions of the machines. You see, the VMs were shiny and new but their names weren't. Once the static DNS records were deleted I could remote! Adds weight to the argument that VMs should be named generically.
The problem with this issue is that problems with PS-Remoting are common place but if you look closely at the dreaded red text, the VMs were returning a 403 error? Authentication maybe? So I started looking down the road of permissions; No joy!
It wasn't until I went back to basic pings and ipconfig until I noticed a discrepancy with DNS – I guess I just took It for granted that as DNS was integrated into AD that it would update? I manually removed the DNS records and allowed the VMs to re-register themselves, however, this still doesn’t explain why the records are not updating automatically? And would this issue reoccur if the VMs were trashed/re-deployed using the same name?