The Server Pool Does not Match the RD Connection Brokers That Are In It. Errors: 1. Cannot connect to any of the specified RD Connection Broker servers

2016 RDS frustration with connection brokers.

This issue comes up if you disable TLS 1.0 on server 2012 R2 and 2016 or your database is in pending recovery mode.

To restore TLS 1.0 or a better solution is update to 2019 which supports TLS 1.2

Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\Schannel\Protocols\TLS 1.0\Client]
"DisabledByDefault"=dword:00000000
"Enabled"=dword:00000001

[HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\Schannel\Protocols\TLS 1.0\Server]
"DisabledByDefault"=dword:00000000
"Enabled"=dword:00000001

If TLS is not the issue then go to this article at RDS Gurus site from Kristin L. Griffin

https://www.rdsgurus.com/rdms-problem-1-the-server-pool-does-not-match-the-rd-connection-brokers-that-are-in-it/ 

Your welcome for disabling Ads, they are ineffective.