Most sources suggest that neither was the case and that Newton's knighthood came about purely as a piece of electioneering by the Earl of Halifax, to boost Newton's chances of being elected to Parliament.
Halifax wrote to Newton thus:
"If the Queen goes to Newmarket, and from thence to Cambridge she will give you great Assistance. The Torys say she makes that tour on purpose to turn Mr Ansley out".
Shortly after that, while visiting Cambridge, she surprised Newton by knighting him (but he still lost in the parliamentary election).