Depends on where the lifter failed...if it's internal in the lifter, the cam may be fine. If there's a problem with the roller like I mentioned earlier, the cam could have sustained damage. Only way that I know to tell would be to pull the cam and inspect.

 

I've heard that noise before & it was the roller on a lifter. It will also take out the cam. The only way to be sure is to remove the valve covers & see if you can isolate which lifter it is. You will have to surpport the coils out of the way of the moving valve train. I would try to narrow the side to one side.

 

My motor sounded like your first video, and I had one ruined lifter and one ruined cam lobe, two cam lobes on the way out, and I forgot if it was one or two ruined main bearings. The bearings were damaged by the ground-up cam metal. It didn't get to sound as bad as yours in the second video, I think you should not start your motor anymore.