> They want to do things their way... Hard to wrangle them

This can happen when the software group is seen as incapable, unresponsive, or even just slower than "business speed". I'd suggest talking to the individuals and their leadership (separately) to learn more about why they adopted X without talking to your department. You may well uncover missing or broken lines of communication, entrenched negative expectations ("it takes a month to get a simple DB query run, why would anything else be faster?"), and/or find processes so onerous that everyone tries to avoid them.