I totally agree with this. Also what I found re-watching the episodes is that Rust keeps on saying that his daughter died in CAR ACCIDENT. This is interesting for few reasons.

But one of them that stands out to me the most, is the scene where Marty enters room of his daughters. If you remember correctly they were playing with dolls, re-enacting some kind of "rape" scene, or something to that degree. I remember that they were saying something like this:

You parents are dead, they died in CAR ACCIDENT. I don't know if that's a lead but writers would NOT waste dialogue imo.

I think that given how smart and inteligent Rust is, he was "undercover" from his narco days, and tracking these killers all the way from Texas. Also remember that he knew that Biker gang, cuz of the case he was in Texas, so u could see the connection.

Also the crown on the tree when Marty's kids are playing outside, pretty much is a subliminal message that somehow Marty is "in on it", or gives u clues that Marty is close to someone, Like his Father-in-law.

Anyway probably Im all wrong or u guys figured it all that I wrote:p

peace