Thanks for adding this. I suspect that the privately owned service roads within Glengall Business Centre should be tagged with access=destination + ownership=private. That should prevent routing software from using it as a short cut between Old Kent Road/Ossory Road and Glengall Road. Assuming you're more familiar with the area than me, does that sound like a reasonable description of access there?

https://wiki.openstreetmap.org/wiki/Tag:access%3Ddestination