Simply put this research at this stage proves nothing, however it could indicate an area requiring further analysis, but that's about it.

"Correlation does not imply causation" https://en.m.wikipedia.org/wiki/Circular_cause_and_consequen...

It's really easy to see that lots of reasons that aren't directly due to the program could have caused the changes. It could have been as simple as an expectation change amongst the parents, upon joining the program; how their children will perform better and therefore they did or it could have been the parents in the neighborhood most engaged in their children having a better life and when the opportunity to join the program became available they joined.

Stuff like this is notoriously difficult to prove, but I'm hopeful and glad to see research is being done.