Odd URLs and Indexing Issues

Hello. I have an odd question regarding some strange URLs that Search Console is not accepting the redirects for. I have no idea where these came from or how they could have been created in the first place. I'm not new to SEO, but I'm no expert either.

These URLs are structured as follows (Obviously not a real URL):

https://www.examplesite.com/blahblahblah/https://www.othersite.com

The URLs have been redirected, but I'm still getting a fail on the "Not found (404)" validation. If anyone has any info, it would be greatly appreciated!

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