Shocking fibre install through lawn

The above picture is the state of my parents lawn after VM installed the fibre from the pavement to the house. This install was completed about a month and a half ago which initially didn't work at all. I visited today and was in disbelief at the fibre just sat on the top of the lawn, the trench can't be much deeper than 2 inches! I spoke to one of the neighbours after seeing a channel in their lawn but the cable is actually buried properly, they said the installers actually hosed the grass to wet it as they dug and buried it, whereas they didn't when digging my parents dry lawn. Is there a way I can get someone to come out and actually bury this cable properly??

TIA.