Adding alt text to images and mastheads in Adobe Captivate Prime

We are currently implementing Adobe Captivate Prime as our LMS. One issue we can't seem to get an answer for concerns alt text. As a public institution, we are required by law to be compliant with all WCAG guidelines and requirements. We have not received a clear answer on being able to add alt text to training card images, course banners, email banners and announcements/mastheads. Any help would be appreciated.