std::dynamic_pointer_cast<TraCIEnvironmentModelObject>(objPtr);
traciObj->getVehicleData();

Seems like this piece of code in CpService requests a type present in envmod, which fails loading the core shared library on any scenario start. Interestingly, this issue also uncovered my misuse of test runner - it prints errors, here

runner = unittest.TextTestRunner(verbosity=args.verbosity)
result = runner.run(suite)
result.printErrors()

but it never changes status, which means that even if errors were found tests on CI will pass anyway.