The ones I know:
- Grimsborough Menu Theme - original by Pretty Simple
- Grimsborough Crime Scene - original by Pretty Simple
- Pacific Bay Menu Theme - "Sleepless (Remix Instrumental)" by Plastic3
- Save The World Crime Scene - "Suspense Detective Crime" by Leran Wang
- Supernatural Menu Theme - "Cursed Relics" by Diamond_Tunes
- Paris Menu Theme - "Paris Waltz" by RockMeister
The ones I don't know:
- Pacific Bay Crime Scene - ???
- Mysteries Menu Theme - ???
- Mysteries Crime Scene - ???
- The Conspiracy Menu Theme - ???
- The Conspiracy Crime Scene - ???
- Travel In Time Menu Theme - ???
- Travel In Time Crime Scene - ???
- Supernatural Crime Scene - ???
- Paris Crime Scene - ???
The ones I know, but haven't found:
- Save The World Menu Theme - "Epic Heroic Trailer" by EgorBug (only saw it on AudioJungle with watermarks)
Except for the first season, all of them appear to be ad-licensed royalty free music (even in the game form, they don't get taken down from YouTube for copyright infringement). They're hard to find though, Google and other sound search haven't been able to locate them.
EDIT: Supernatural's menu theme was only recently recognized and added on the YouTube database after already existing for years, so I suppose it's the same situation with the others, the only way to find them would be to know their original source.