I had to allow all the IP's of the management network on my firewalls, three in total to get this to work. So for me it was...
172.24.3.25 - Management
172.24.3.26 - Controller A
172.24.3.27 - Controller B
Initially I only allowed the Management IP out through the firewall. After adding the controller IP's my vCenter showed up. I had to do this for both my primary and DR Nimble's.
Thanks Chris! I don't have anything blocked outbound. But I just checked 5 minutes ago and VMVision is working. Either it took its time(5 days) or nimble support did some background magic. They did do some maintenance on infosight during the weekend, so maybe that's why it took so long.