Tile acting up

Our tile is acting up.  And by acting up I mean playing games with our eyes.  We wanted a grey and white carrera marble tile for the bathroom, and what's happening is more of a dirty yellow and grey tile look as we think the thinset is seeping through the tile. 

We ended up cutting out the tile that was put up because of the yellowing that we saw.  Goodbye, $$$$!  Yikes.  Here's the aftermath as it looks outside.  Notice the lighter tiles are a bit yellow.

It really looked yellow in the bathroom.

So we are in the midst of an experiment.  Two samples: one with a bright white thinset made for glass and the other with a more grey color thinset to not allow for the yellowing to happen.  Here's what they look like now.

White:

Grey:

So for I think the white is winning.  Notice on the grey sample, it looks like a grease track in the middle of the tiles.  That's what the entire wall looked like last night (and that's what was removed today).  We think something is seeping through and I hope it is the thinset (and not the glue backing on the back of the tiles).  We shall see what happens with this experiment.  Worst case we have to buy new tile and take this back ... which will add lots of time.

It's a very special day for Ethan - he is 10 months old!!  And, I think the shot he had to get last night (to help with his ears) is helping him to feel better.  This is the smiley baby I know!  That's his toy phone he is waving in front of his smile.  Just love to see that he is feeling better

Can't believe it's been 10 months - WOW!