Hi @Pattrix,
Welcome to Q&A!
Based on my test, it looks like it is a by-design behavior for external or guest users that unable to view the speaker's profile picture.
Following is my test result:
There are 3 users in the test: Sharon is the organizer, Jimmy is the attendee in the same organization, Alex is the external user.
After Sharon started the webinar, Jimmy and Alex joined it.
In Sharon's interface, she could see the profile picture of Jimmy and herself, but not Alex's.
In Alex's interface, he could only view his own profile picture, but not the picture of Sharon and Jimmy.
Please feel free to let me know if you are in the same situation. If not, to have a better understanding of your problem, please kindly share some related screenshots with us.
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