In the first 15 minutes the grout taken down the hole was 24.00 cu ft [680 litres]. This is a very large take.
This grouting was done with 0.8:1 grout. It is obvious that the hole will take thicker grout without getting blockages. So it would be sensible if you thickened to 0.6:1.
It is necessary to decide what to do next. The choice is from one of the following: