Hi Brigitta Nuccio Welcome to the Canvas Community. Based on test I just now did in a sample class to confirm this, they will only see the most recent submission. As you may have seen for yourself with group work when accessing SpeedGrader, by default only you can see the most recent submission with any group work, as well, unless you click to see the previous submissions. (And even then, you cannot tell which student submitted it unless there was a name on the submission.) Students do not have that ability in their peer reviews.
As I always say to faculty members at my own institution, whenever you want everyone to submit something for an assignment, you do NOT want to use a group assignment to do that in most cases. Canvas will always regard group submissions as something done on behalf of an entire group.
(In fact, with all group assignments, the second student (and third, and fourth....) to submit something for the original group submission will see a Re-submit Assignment button rather than a Submit Assignment button.
I hope this helps, Brigitta!
Thank you for the helpful information.
Glad I could help, Brigitta!
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