Granite Polishing Question Please Help!

Dear Findstone.com,

I am writing because I have granite countertops and a full wall backsplash in my kitchen recently installed and worked on. The installer albeit a handy-man grinded down the seams (two on the counters) and one across the backsplash near where the hood is located) with the diamond-pads, water and an electric grinder and worked up from 400 to 1300 grit paper (he might have also used some 3000 but I'm not sure). But the granite still looks dull at the areas he worked on! Is there any type of polish that can be applied to give those areas the same or similar luster appeal as the other un-touched areas? I have consulted with a few places one said they can polish it out with a higher grit paper costing somewhere between $120 to maybe $400 if its a 2 hour or 4 hour job, and another said they can do the same although it would be extremely difficult to get the luster back and it would cost $2,000 unless he just applies a wax that would last for some time but would need to be re-applied again. A third granite installer looked at the areas and he said the backsplash is impossible since water cannot stick vertically so I can't do anything with that! The granite, I believe is called Lady Luck from the distributor where I purchased it from but on your website seems closer to Agate. I think my backsplash near the hood is ruined and don't know what to do to get it's luster back.

Thank you ahead of time for your help.

-Andrew