Segfault on Catalina with C++ extension

We have a user running a custom PyFi extension that is segfaulting. I'm able to reproduce this on my OSX laptop with Catalina. It does not seem to occur on lower versions of OSX or any other OS. 

The segfault occurs when the method in the C++ kernel file is called from within the PyMOD file. However, error output is showing that the crash occurs on another thread. 