Travertine Floor Holes

We have recently moved into a new house with a travertine floor in the kitchen. Recently we have noticed pin holes appearing in the floor which then crumble to 2.5-3.5cm across. The floor has been sealed & we have underefloor heating. The flooring contractor have advised that these holes can be filled & the floor treated with a chemical hardener called "SK40" which will help stabilise & Harden the floor tile. I would be most grateful if you could give your opinion on this course of action becuase we are unsure how effective it will be.

 

Thank You

 

Katy & Jeremy