/ip firewall layer7-protocol
add name=testdns regexp=xiaocaicai.com

/ip firewall nat
add action=dst-nat chain=dstnat disabled=no  dst-port=53 layer7-protocol=testdns protocol=udp to-addresses=8.8.8.8 to-ports=53
add action=dst-nat chain=dstnat disabled=no  dst-port=53 layer7-protocol=testdns protocol=tcp to-addresses=8.8.8.8 to-ports=53


1. Change the regex to match your domain.
2. Change 8.8.8.8 to be your AD DNS server

参考文章