Hi Patrick,
Thanks for the form. In your xls form, I can see you are using quite a lot of hidden fields, caluation, and pulldata funtions, which might potentially impact the behavior you are seeing in the Inbox.
The image question is not availalbe in Inbox due to this enhancement request:
ENH-000110614 Add the ability to allow additional attachments to be added when attempting to edit and resend surveys in the Survey123 Field App
I'd suggest you to contact Esri Support to have them help you troubleshoot the issues individually and also attach your case to the existing enhancement request of the Inbox images. This helps us assess demand for the enhancement and prioritize it accordingly.
Thanks,