Thank you for your post.
Your Quick Find formula "Scenarios::SC UC Link = $$SCID" evaluates to either True or False. Since you are currently on the third record, the formula will return False, no records are found, and a 401 error will appear. Instead of using Perform Quick Find, use the following:
Enter Find Mode [ ]
Set Field [ Scenarios::SC UC Link ; $$SCID ]
Perform Find [ ]
Let me know if you need additional clarification.