Make sure that the vRNI Proxy (Collector) can reach the CP Management Server on port 443, so open up any firewalls between those endpoints as well as configuring the CP Management Server.... Manage & Settings > Blades > Management API > Advanced Settings. From the vRNI Platform...go to the Add Data Source page for Checkpoint and input Administrator credentials with Read Write permissions.
are you shure that write permissions are needed to add the Checkpint Management Server / MDS to vRNI?
I think many customers don´t allow systems to get full access to the central firewall management server.
Read-only should be preferred.