Please collect the device SNMP walk file to check the value of vsxStatusCpuUsageTable (188.8.131.52.4.1.26184.108.40.206.2). If the device SNMP walk file doesn't have any entries for this OID or the value returns 0, this means the device is not sending any data or sending incorrect data for the VSX CPU usage.
There is a known issue for Checkpoint that SNMP query for CPU usage by each Virtual System (OID 220.127.116.11.4.1.2618.104.22.168.2) returns 0 (zero) values. Please provide this CheckPoint link to the customer in order to contact the hardware vendor to get the fix for this problem.
Alternatively, there is a workaround for this in Spectrum. We can use Performance tab of each virtual system, which reads VSX CPU usage for all the CPU instances from HOST-RESOURCE-MIB [hrProcessorLoad 22.214.171.124.126.96.36.199.3.1.2] and populate to the graph.