Alright. After quite a bit of back and forth with different opinions on whether or not you should be getting compensation, we have come to the following conclusion:
As most people in this community already know, compensation usually does not happen for "what if" scenarios! In this case however, I have decided to go about it differently and here is why...
In the video evidence on the report it clearly shows that You did indeed take that step forward only to hit into thin air and also had plenty of time to lockpick the truck without anyone turning up to stop you. So my conclusion to this is, that there was nothing stopping you from getting the money, except for Mr. Mitch combat logging on you.
Therefore you will be compensated 636,520 pounds, as that is the amount that you lost out on.
I would like to clarify that the circumstances of this incident were quite lucky for you and these requests are usually denied rather quickly.