Clients not picking up DNS

Hi All,

I have tried for some time to get this working but hopefully someone out there will know how to solve the issue.

I am trying to get Link working to roll out to clients so we can remotely manage their machines. At first I just had the PDQ Link Server using a range I gave it to give out IP's but the clients werent getting DNS and when I logged a ticket with PDQ Support I got the video of how to install PDQ Link which was using DHCP. So.. I decided I will do the same so installed DHCP and it seems to be working as it gives out 10 address leases to the Link Server (Is this correct?).

Re-ran the client setup and can ping the IP addresses of the servers on the network but cant ping back (except the link server) and it is not registering in DNS either. What am I doing wrong? 

The PC Is a domain joined PC and the user is a domain user. It connects, I can see it in RAS and everything it just wont submit its IP to DNS and it is driving me insane.