The dominant pole is located at the output of the first stage, because that’s the high impedance node. The output node as low impedance due to the source follower.
The second pole (non-dominant) should be defined by the output resistance of the source follower and by your load capacitance. Therefore, increasing the load capacitance should worsen the PM...
The previous comments are true, unless you have a very big load capacitance, which would make the output pole dominant...
The schematic showing the way you are connecting the amplifier, to measure the ac parameters would probably help. And the value of CL, op data would also help...