I think the idea is to use an entity that you don't have any sort of formal agreement or paperwork with. Eg. work out a verbal agreement with an old friend that you trust, send them the insider info in an encrypted or analog way, then they send you a cut through some unrelated method. That all seems plausible for a normal motivated person to execute on and very hard to prove.

Congratulations, that's now a conspiracy to commit insider trading.

Well, yeah, that's the point. We're talking about ways insider traders can evade detection.

I think the idea is more like "get my acquaintance Bob to go to his broker and make the trades based on my information, Bob and I split the profits under the table."

The SEC can collect all the information it wants, but people committing securities fraud may not provide accurate information.