Echoing everyone's outrage here. That curb is a nightmare. As far as the grout goes, you can paint on a grout colorant made by Mapei called Grout Refresh that will make it look uniform. You'll have your work cut out for you will all that penny tile but it may dull the pain of your $27,000 screwing over
https://www.amazon.com/dp/B006IS9B2G/ref=cm_sw_r_cp_apa_fabc_oKL4FbM1GHADF
Funny this would pop up a week after I figured this out.
I just redid my bathroom using https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.amazon.com/Grout-Refresh-White-8oz-Bottle/dp/B006IS9B2G&ved=0ahUKEwin0tPV6r_SAhUEw2MKHTArDRwQFghWMAA&usg=AFQjCNH_d6V1ns9a1orXqDmb-c3WgxSPWA&sig2=1p4PhR4Rv6E64...
The results are amazing. It's a pain to put down and scrub in. It's like a paint, but since I have vinyl tiles it was real easy to wipe off the excess.
Glad yours worked out with an easy solution.. I wanted to scrub mine but it was real dull looking. This also seals. Will have to see if that's true