I have not read the paper, am not an expert, and can't judge with 100% reliability - but my understanding is no, I don't think an experiment of this type will n

I have not read the paper, am not an expert, and can't judge with 100% reliability - but my understanding is no, I don't think an experiment of this type will necessarily provide the insight into a quantum nature of gravity. The effects described here are purely Newtonian - in particular, the earth's rotation and gravity are the same "kind" of impact, just an F=ma force which deflects the beam of molecules in the same manner that gravity deflects a stream of water out of a garden hose or the earth's rotation deflects a Foucault pendulum. In general I think I quantum gravitation experiments would require very low-mass particles in a very high-mass gravitational well: high-mass particles on Earth will be dominated by Newtonian gravity and quantum effects will be extremely difficult to detect. The relation this does give insight on is between Newtonian and quantum physics - the fuzzy boundary between determism and randomness - which is itself interesting, but also better understood. Perhaps a more precise measurement may reveal that the gravitational deflection is significantly more/less than expected from classical gravitation in a way that can only be explained with a new quantum theory, but that is quite speculative and almost certainly not supported by the evidence in this particular experiment.