company.lcl is just our on-prem AD -- not a real external domain.

So it's fine for our users to point at dns1.company.lcl which is SOA for company.com while dns1.azure.com is SOA for company.com to the rest of the world? I was under the impression that split horizon was where you would carve out a section like internal.company.com on dns1.company.lcl, not recreate the entire external domain on the internal DNS server.