Having trouble calculating incoupling efficiency for an angled grating coupler

[madyellak]

Hello!
I was originally running simulations in Lumerical to calculate the incoupling efficiency for an angled grating coupler in which I used a field monitor in the waveguide for transmission, so I tried to apply that logic to Meep and decided to do two runs:

1. Normalization run to get input flux
2. Geometry run to get flux through the waveguide

Then I would take the flux from the geometry run and divide it by the input flux. However, my results between the two simulations do not seem to be matching up. I was wondering if anyone could check my logic? Thank you!

Normalization run:

Geometry run:

Also if anyone had tips in general in trying to match simulation results between the different software's that would be helpful!