Grout issue

[tomredsky]

Hi,
We recently had these floor tiles laid and I am trying work out what's wrong with the grout. I hope it's clear from the picture, the grout is beige but some parts look grey and I suspect the grey is the cement. Beside getting the tiler back (I expect that would be fruitless), what is the remedy? Remove as much material as I can and re-grout?
Thanks in advance.

 

[Wayners]

Grout is completely different colour.
Not a spill that needs washing off? That's what it looks like.
Soda and vinegar or escalate to to grout cleaner if soap and water don't work

 

[stevie888]

Is it grout or an excess of adhesive?

 

[tomredsky]

I tried the soda and vinegar. I did it twice on a small section to be sure but that made no difference.

>Is it grout or an excess of adhesive?
I don't know.

It didn't starting out looking like. The tiles were laid about 3 months ago. No one recalls spilling anything on them either.
There's a couple of close ups in case there are clues.