Internal Magnetic Field Boundary Condition with RF module

Hi! I am attempting to create an internal magnetic field boundary condition in a model with the RF module. (inside a perfectly matched layer)

I am able to do something similar with the electric field boundary condition, with which I can manually simulate a PEC boundary (manually set tangential E fields as zero).

Is there a way to do so with magnetic field boundary condition? (e.g. explicitly define a PMC, without using the PMC boundary condition).

I am only able to set the magnetic field boundary condition on external boundaries.

Thank you so much!