Here are some details about what the BMC status command reports. VRC is the voltage regulator controller on the RCK chip.
1V0: 1.020 V 1.430 A FPGA voltage
1V1VCCA: 1.104 V 2.450 A Voltage for analog portion of Memory controller
1V1VCCT: 1.094 V 4.639 A Voltage for system interface (SIF) and digital portion of memory controller
1V5: 1.516 V 8.322 A DDR3 voltage
1V65: 1.776 V VRC scan voltage
1V65ADJ: 1.656 V Alternate VRC scan voltage
1V8PHY: 1.810 V PLL reference voltage
2V5: 2.488 V Auxiliary FPGA voltage
3V3: 3.336 V 1.790 A Various Copper Ridge (or Rocky Lake) board reference voltages
3V3SCC: 3.308 V 20.594 A Input voltage to VRC- this feeds the core voltage regions and the mesh network
OPVR VCC0: 1.0947 V Output voltage of VRC to Core 0 region
OPVR VCC1: 1.0962 V Output voltage of VRC to Core 1 region
OPVR VCC2: 1.0994 V Output voltage of VRC to Mesh network
OPVR VCC3: 1.0948 V Output voltage of VRC to Core 2 region
OPVR VCC4: 1.0971 V Output voltage of VRC to Core 3 region
OPVR VCC5: 1.0945 V Output voltage of VRC to Core 4 region
OPVR VCC7: 1.0940 V Output voltage of VRC to Core 5 region
Is there a way to get current from the tertiary voltage controllers?
I don't think so, sorry.