You should be able to just hook the SDI output from the CCU directly to the SDI inputs to the scope. Pretty simple. Just make sure that you have the CCUs set to output SDI from the connectors and not VBS. I don’t know if this is a jumper setting or a menu setting on this CCU, but there should be a way to switch from one to the other. Check the CCU to see what way it is currently set. If you are using the cameras in an analog environment and have to stay with the VBS outputs, you may need to get an analog to SDI transcoder of some sort to feed the scope using one of the analog outputs. If there are RGB outputs from the CCU that would be your best bet for transcoding to SDI.
Tom