I tried using the Repeating Section Content Control like you suggested. The issue is that I need the plus button there for the user to be able to select. With the form locked, that plus sign is not there, telling me this is only available while protections are not in place, and I cant have an unprotected form sent out as a company document.

Currently I have 2 forms as a workaround that allows up to 3 devices or up to 6 devices. I'm still interested in figuring this out as this would make the form look much cleaner and simplify the process, instead of having to have 2 forms. Again, I appreciate your help!

EDIT: I also tried out the date picker content control with the same form using legacy forms and so far it has had no issues. I have another person testing it and it seems to work just fine. This goes to your theory that using both types of content controls doesnt cause issues.