Okay, we have a little confusion about. Let's dissect!
First of all, the grip safety on a 952-1 is NOT like a 1911 in that it has no bearing whatsoever on the fall of the hammer. It is fully operational as designed for a 952-1/952-2 to drop the hammer when trigger is pulled no matter what the grip safety is doing.
On the 952-1/952-2, the grip safety deactivates a firing pin lock and nothing else. The proper test for a 952-1/952-2 grip safety is a pencil in the barrel. I recommend eraser end toward breech face. When grip safety is squeezed and trigger pulled, that pencil will find your ceiling.
Pull trigger with no grip safety and the pencil travels nowhere.
On your other issue (magazine disconnect safety) I must agree that your pistol is not in as-designed operation here. I will say (with no reserve) that a truly malfunctioning magazine disconnect safety in a S&W is, in my experience, a statistical anomaly-- that is to say that unless someone specifically altered it (happens more than you might guess) then you are experiencing a RARE EVENT.
Nothing is perfect but across many dozens of S&W pistols, I've never witnessed this first hand.
My first guess is that a previous owner got under the rear sight and altered the pistol to bypass the magazine disconnect safety. For a target gun... well, I'll side step that forum "can of worms" and merely say that I approve!
Try the pencil test for the grip safety.
Oh and one last thing... absolutely MY own opinion and speaking for nobody else...
I personally believe that sending a 952 to S&W in the year 2017 is about as silly as sending it to Ruger or Beretta for service. I doubt there is anyone working there that has half a clue what a 952 actually is. Simply put -- no way, NO WAY would I send that gem to those guys.
I can hand pick five guys from this discussion forum that are better qualified to make a 952 work than Smith & Wesson circa 2017.
Please report back! Your pistol is a sweetheart and probably closer to "ready" than you think!