Nearest neighbor destination to source interpolation for runoff

The port of mpas-ocean into the CESM framework is not getting all of the runoff (rofl) from DROF. I believe this is due to the mpas-ocean grid not being global - only defined where there is active ocean. With offline testing I have found that a nearest neighbor destination to source interpolation will conservatively interpolate the runoff to the ocean grid. Currently, I do not see this option in med_internalstate_mod.F90.
Right now, as I see it I need to:
Add a nearest neighbor d to s option in med_internalstate_mod.F90 based on ESMF_REGRIDMETHOD_NEAREST_DTOS (I propose mapndtos).
Add a block to med_map_mod.F90 to call ESMF_FieldRegridStore for this interpolation.
define rof2ocn_liq_rmap somewhere so that it is not 'unset' in esmFldsExchange_cesm_mod.F90, but is set to mapndtos.
I've likely oversimplified and am missing things as well.