Thank you @danielt. ARMs juno platform seems to be perfect fit for my work. I have also been looking at Minnowboard Turbot schematics and it seems that the resistors have been surfaced on the board to tap. Do let me know if you know about other alternatives. I will make a evaluation and buy one of them.
The NI measuring modules to measure current has a built in shunt resistor. It also has very low input impedance (12mOhms). So, I strongly believe that it should be within the PMIC's design constraints as the voltage drop across it is negligible.
We recently bought Nvidia Jetson TX1. But the schematics for the daughter board are not available. Also, the Thermal Transfer Plate (TTP) is applied in a special process which once taken apart cannot be put back together without specialized equipment. So, there was no access to PMIC there.