When the business parking is shut, there is no access to the outside world. (This is the normal situation as far as I am aware). If the car park gates are unlocked outside office hours, suggest that you moor up against the wall away from the wharf.
There are no boaters facilities at this mooring. (There aren’t even mooring rings, unless they are so buried in the undergrowth that I couldn’t find them – I tied up to the trees)