Sounds like they kind of reached a "crap or get off the pot" moment. They need to be able to design and code these games with their in-house guys, and not be reliant on external (possibly unpaid) members of the community. There's potential legal issues there as well, and it may have been a condition of one or both license holders not wanting someone not on the payroll being involved. This isn't necessarily the end of the world, or even a BAD decision necessarily, but like someone stated above, it does raise a few questions, especially given that some people feel that ACNC was left unfinished (and I don't keep up with ACNC stuff, I've just seen it mentioned here and there).
I think if anyone is or was expecting Lyman level code where there's such ridiculously arcane things (such as knowing the release order of AC/DC's albums) to affect scoring....they were going to be disappointed no matter what it ends up being. Lyman is a freak of nature (in the best way possible!), plain and simple. Personally, for me, I'm cool with the more "basic" code archetypes of like AFM/MM/Stranger Things, but these games already look like they're trying to be more complicated than that. As long as the modes make you shoot varied shots and aren't too easy to complete (strict timers, wide shot variation making you shoot specific shots in a sequence, or create specific combos), I'll be happy. Let's be honest here...... it's pretty hard to innovate in pinball rules. Most games that aren't Lyman games follow some long-running patterns, and even on Lyman games the "exception to the rule" part is frequently limited to scoring for the wizard modes. Metallica was an awesome game, but very little there that I would say was "innovated" aside from Crank-it-Up modes and their contribution to scoring.
That updates keep bricking the games to the point that you have to go to support is far more concerning to me than the current state of the code.