If a knowledge of Pro-Engineer or related CAD/CAM design software is their main criteria for hiring, they aren't looking for an engineer, they're looking for a CAD/CAM software operator. The best engineers I know don't rely on high-end software, they use their minds and experience, and can do more on the back of a napkin with a pencil than any hot-shot fresh out of school workstation jockey with the latest whiz bang software.
Could be that they are looking for a plug-in writer which
would require some familiarity with coding to some API.
Of course, any reasonable C++ coder should be able to do that but they want minimum learn curve.