IPSEC VPN DNS domain forwarding

Hi,

i have the following Scenario:

2 Fortigates

Fortigate1 is our Firewall in the Main Company

Site-to-Site IPSEC VPN Interface Mode

On Premise DNS Server behind Fortigate 1

Fortigate2 DNS Server

The VPN is working. I can reach the Clients on both sites.

With a Lancom Router it is very simple to solve.

Now i just want that all Nameserver request with the domain wildcard *.lan.local goes over the VPN and asks the DNS Server behind the Fortigate1

All other DNS requests like to google. com should handle the DNS Server on the Fortigate to.

I tried almost all Configurations but im only able to to forward all dns requests over the vpn or all over the fortigate2.

Regards Gordon