Using Keysight's Advanced Design System EDA, I created a basic model of the bandpass filter as it currently stands on the pull-out-structure:

This compares very closely to the measured values from the NanoVNA but is distinctly different from those from a simulation of ideal components:

I am currently considering two options:

1. 1. 1. Institute a high-pass filter instead of the bandpass filter and cut off harmonics after the PA with a phyisically bigger filter
      2. Utilize a band-stop filter to reduce the cutoff that the bandpass filter must have to eliminate the 105.6 MHz unwanted mixer product.