What is best to fill and smooth this?

[SuzanneC]

Daughter wants to put a fresh bit of vinyl on loo in new house. It's downstairs and was previously dug across, presumably for plumbing from outside boiler house adjacent.
Middle bit of trench is roughly level, just slightly above level of old tiles in a couple of places. The bit at the door however has crumbled. The bit at the far side, sorry pic is dark, was stuffed with tissue and is about 2 inches deep.
What would be best for crumbly bit to stabilise, and the larger hole?

 

[Astramax]

Fill it with Toupret Masonry Repair Filler, Screwfix stock number 572PP or if larger quantity required stock number 893PP, fill, let dry and sand smooth. Follow instructions on packet.

 

[SuzanneC]

Fill it with Toupret Masonry Repair Filler, Screwfix stock number 572PP or if larger quantity required stock number 893PP, fill, let dry and sand smooth. Follow instructions on packet.

thank you