Just one big caveat here. By launching JMP via COM from another Python process, you are not directly able to take advantage of the import jmp or any of the new functionality built into JMP 18 and JMP 19.
Though if your JSL scripts call Python Submit() or Python Execute(), then your Python launching JMP to run JSL could wind up calling the Python within JMP... which could well be different than the Python you are executing from...
Sounds like you are driving JMP via external process through COM.