The authentication approach (username / password) is not a secure approach to connecting to MS Dynamics, and goes against Microsoft's recommended approach.
Microsoft recommends you do not use the ROPC flow. In most scenarios, more secure alternatives are available and recommended. This flow requires a very high degree of trust in the application, and carries risks which are not present in other flows. You should only use this flow when other more secure flows can't be used.
https://learn.microsoft.com/en-us/entra/identity-platform/v2-oauth-ropc?WT.mc_id=AZ-MVP-5001507
Can you either add the ability to use alternate authentication approaches, or allow the developer to override the methods and deliver their own.
We currently need to develop our own MA connector due the security concerns expressed by the client.