This is the most relevant section of that report for me...
"It is clear from text message records and witness evidence that the pilot
knew before flight that there was fog at Elstree Aerodrome. In a telephone
conversation with a colleague at 0649 hrs, he said he was going to cancel the
flight because of the weather despite feeling under pressure to continue with
it. At 0706 hrs, he reportedly told Witness A that he intended to fly over Elstree
to check the weather for himself and, at 0729 hrs, he sent a text to the client
saying that he would be “coming anyway will land in a field if I have to”. "
It clearly shows he changed his mind, probably due to being pressured, “coming anyway will land in a field if I have to”. and this is the start of a very bad day.