Sorry you NEED to point to your AD for dns - maybe there is something wrong with it resolves outside domains slow. FIX IT!!
How do you resolve your AD records if your not usnig its DNS? 18.104.22.168 does not know about it for damn sure.
If your AD is having issues with resolve outside domains - then you Need to FIX that. And yes not pointing to your AD dns could cause all kinds of issues like not being able to auth to stuff, stuff being disconnected, not being able to log in or taking a LONG time to, etc. etc.
Having issue finding the MS article that lists it as one of the top mistakes, but here
10 DNS Errors That Will Kill Your Network
TCP/IP Configuration Points to Public DNS Servers
This is by far the most common DNS error. Each network interface has a set of TCP/IP settings that lists the DNS servers used by that interface.
If the TCP/IP settings for a member computer specify the IP address of a public DNS server—perhaps at an ISP or DNS vendor or the company’s public-facing name server—the TCP/IP resolver won’t find Service Locator (SRV) records that advertise domain controller services, LDAP, Kerberos and Global Catalog. Without these records, a member computer can’t authenticate and get the information it needs to operate in the domain. It then acts like a teenager who can’t get the car keys, growing sullen and exhibiting a variety of bad behaviors.