Throw down floor drying panels and put vacuum on it.
Or at least poly sheeting (6-mil) and pump process air out of an LGR dehumidifier to draw moisture out of it.
Is there a basement or is this a crawlspace? If basement you need to contain the space with poly, reducing your drying chamber and use the LGR process air.
Upon initial inspection I would’ve used thermal and had the tile pulled. It’ll delaminate with that amount of moisture.What is the distance between holes? They could have used the holes for their moisture meter electrode probes when checking the subflooring.???
That’s why I’m pretty sure they had an issue with hollow tiles or termites. Termites is usually perimeter treatment but I have seen mid floor treatment.this isnt my project, rather a hard Surface Course student's
if it were a too wet grout install issue I would expect other signs, which there isnt.