Hi Nicole,

Based on the date you asked your question, I certainly hope you were able to find an answer by this point, but since I had a similar issue and came across your question I figured I would tell you what I found.  If I want to share a pdf in a meeting and I open the sharing tray I am only able to browse for power point files.  However, if i open the PDF file before joining the meeting, it will be listed under the Window section of the sharing tray.  Also, I found that if I have the sharing tray open and I've already joined my Teams meeting and want to share a PDF, I can minimize Teams, open the PDF file, go back to Teams and then close and re-open the sharing tray and the PDF will be listed to share under the Window section.  Unfortunately, I don't have any advice for your video question.  Hope I was able to help.