Jared Kushner the son-in-law is the one who recommended Strange, says Breitbart.
recommending is one thing, vetting is another. Presuming they are two different functions, Jared might be technically off the hook...
Even so, ...
Trump has no prior political office experience. He brought in his immediate family as advisors. They also have no prior political office experience.
Hopefully we are getting a decoy story. Alternatively, as I mentioned a few posts ago, Trump had to lose some losers simply because he needed some votes on other bills such as (though not limited to) repealing and replacing Obamacare, and someone told Trump that support by Trump for Luther was the price of those votes.
It is all speculation and most of it might be Kabuki. Sometimes I speculate that the current obamacare thing is a feint for something to come that is not quite fully baked yet. I get that sense by (for example) watching Rand Paul talking about Obamacare with the sound turned off. Of course I am totally in flyover country, out of the loop, uninformed, etc.