Well if that’s the granite you have have you thought of getting faucet with hot/cold handle ( looks like yu have that already) then the left hole could be a sprayer and the right side hole could
Be dish soap dispenser. I have dish soap dispensers in my houses no bottle of detergent needed on the counter.

This looks like a bathroom and the holes aren't even drilled for a widespread faucet but for a center set unit. The only choice you have would be to replace the faucet with something like the ones below. I hate centerset faucets as I think they look cheap and are difficult to clean. I'd pitch a fit until the builder got me new granite. If it's more expensive, that's his fault.He needs to correct his mistake.https://www.supply.com/browse?refinements=visualVariant.nonvisualVariant.Brand%3DMoen~BrandCategory%3DMoen+Bathroom+Faucets&nid=2227093&campaignid=234158902&adgroupid=14476231942&adid=53002145062&gclid=CjwKCAiAj-_xBRBjEiwAmRbqYrPCyqtyGk-3MZiGAnDcyz6A4M1QkY2IfAVZztSR8wS-GdG-ae8LFBoCw6UQAvD_BwE

Or this : https://www.allmodern.com/Danze%C2%AE--Amalfi-Centerset-Bathroom-Faucet-with-Drain-Assembly-D301130-L655-K~CBGG1054.html?refid=GX87243775756-CBGG1054_35943666&device=c&ptid=572080740238&targetid=pla-572080740238&network=g&ireid=65259759&mktdc=GXPLA&mktcm=442730956&mktst=26525465596&mktcr=87243775756&mkts=%7Bsk%3A%7D&PiID%5B%5D=35943666&gclid=CjwKCAiAj-_xBRBjEiwAmRbqYgyjPBPOyc34AzqC1cMyvUOSBraXe1Xy7lkVrDrrzWQWHf-f-xb_1RoCzKYQAvD_BwE

I’m guessing that this is a bathroom and not a kitchen, so a sprayer probably won’t work. Agree, the contractor should make it right since it was his error, but , lacking extra granite, I’m not sure how that can be done. Hope this is resolved to your liking.

Or cut a square out of the spare stone you have ..mount it over the wholes like a plinth and mount the tap on top ?

Fortunately that’s a very forgiving particulate. I could make acceptably inconspicuous repairs.

Time to get a new faucet for your 3 holes. Not an ideal solution and very aggravating....

This Delta Trinsic Bathroom Faucet supports many faucet centers and looks similar to your current faucet. I'm surprised the thin hole-cover doesn't allow the spout to face forward.