So if you do not see it (even as an admin)
1) you do not have the correct environment
2) they didn't share it, they simply shared the "play" url which is not the same thing, they need to add you to the app
Verify with the user the right environment
pick the right environment
pick Apps on the left nav
Look for Apps Shared With Me
If you don't see any of that properly they didn't share it, they sent the link to what they would use.
have them actually share it, also make sure you are a System Admin, IN the environment they are talking about. Even so, unless they share it its not gauranteed you can see it and thats on purpose.
If these suggestions help resolve your issue, Please consider Marking the answer as such and also maybe a like.
Thank you!
Sincerely, Michael Gernaey