Well, here is Castlewood Road at its junction with Craven Park Road, but its out-of-date, I'm afraid. (March 2019)
https://www.google.com/maps/@51.5769263,-0.0653158,3a,90y,136.5h,73.28t/data=!3m6!1e1!3m4!1s7fhY2QV4grr16LsSc5nuwg!2e0!7i16384!8i8192?authuser=0&entry=ttuClearly there is a school on that street, hence the restriction. With restrictions like this, we would expect that apart from signs at the entrance to the street itself, there should be placed advance warning signs for motorists approaching on Craven Park Road. So are there any ? I'm afraid you'll have to do some leg work to find out and tell us.
In addition, the PCN may contain fatal errors of content, so please post up all sides.
I have to tell you that it doesn't look hopeful at this point, but if you can do the leg work, better advice can be given.