Blacked-out clips in multicam editing

I was editing away on my MacBook Pro (2.6GHz i7, 16gb, radeon Pro 450 2 GB, Intel HD gfx) using the multicam feature in Edit Page when most of the clips in the multicam clip and on the associated timeline went black. I have no idea why or how to be able to see (relink to?) these images again. Some remained visible and all of the original media in the originals clip bin is visible. So i am baffled. Screengrab below. Can anyone help?
Thank you!

Screenshot 2020-09-16 at 12.58.55.png (624.57 KiB) Viewed 538 times

I'm having a similar problem with a project. One of my multicam clips is blacked out while the other two are displaying fine. Were you able to the solve this problem?