Hi, @Grant Sutcliffe Welcome to Microsoft Q&A, Thanks for posting your query.
As we understand the ask here is to know if any other Authentication Type is supported for the target Azure Server, correct me if my understanding is wrong.
As per the documentation you shared is Azure SQL auth the only supported authentication for DMS V1, In the ADS migration extension, this does not apply as the authentication for the target happens internally through the control plane. So you do not have to worry about target auth in DMS V2. As long as you have access to create the migration in ADS and select the target using their Azure account, the rest is taken care of.
you can refer to this document for DMS V2
Please let us know if this information helps.
Regards
Geetha