I don't think this is as much about "reliability" as it is about the fact that a major studio with ties to Nintendo going back nearly 30 years is looking to grow and branch out, but Nintendo doesn't appear to be an active participant in the process beyond Pokemon. Just something interesting to think about, because it's a very different approach from SIE, who would be involving themselves at the ground level and actively funding/supporting the exploration of new tech and new projects. It does make you wonder just how GF and Nintendo view one another.
They view each other as buisness partners in a Japanese sense? Does this need to be go over?
Nintendo has operated for years based on old timey Japanese trust between itself and it's partners.
SRD being one of the examples, where this company has worked with Nintendo for 40 years and is only brought when the founders decided to cash out (the buyout is likely more of a favour than anything).
Intelligent Systems is technically not owned by Nintendo despite being founded by Yokoi and used to be a internal dept at Nintendo, yet works in its offices but it's mobile policy (FEH) is divorced form the wider Nintendo mobile philosophy (where IS went in hard right from the start with gacha and fanservice as per a normal Japanese mobile game). The status of IS (this also applies to Creatures Inc) comes from the old 70s-80s Japanese practice of making a trusted employee lead a company of their own, both as a way of rewarding that employee with wealth and status, with the implicit understanding between both paryinrd that the ex-employee will manage their new company in the interest of the "boss" who elevated him (and it's almost always him because its Japan).
Even outside companies like Camelot and NDCube always get to develop the new Mario sports/party games, despite the fact that sales and reception of those series have their ups and downs. This type of implicit trust relationships is how Nintendo managed all its "un-owned" partners.
This applies even with their western "un-owned" partners, looking at how they go back to Rare for fixed IP (everything DK plus more) until it's founders wanted out, the same happened for Next Level (Luigi Mansion,Mario Strikers) until those founders wanted out too, and they also treated Mercury Stream the same way (everything 2D Metroid).
People outside Japan say Japanese companies act in a certain old-fashioned Japanese way where business relationships mostly built on relationship and trust than hard contracts, thought they do contracts nowadays after learning the hard way with Yamauchi bring too loose with contracts, to the point of not looking at what he is signing. Yet the legal apparatus is intended to be a nuclear option than a starting point of discussions for Nintendo. To Japanese companies in Japan ...they see Kyoto Companies are even more "old fashioned Japanese" than they are. Nintendo is a prime example.
With regards to GF specifically and Pokemon. Nintendo owns the entire trademark solely, and this makes them the strongest in terms of power relations if things go south (aka nuclear option), which it wouldn't because that isn't usually how Nintendo operates. If GF really cuts loose, they stop being the able to develop Pokemon games or even touch the IP, and most likely TPC will be dissolved given that Nintendo can withdraw all rights for TPC to do anything with Pokémon so GF and Creatures share means nothing. This also applies to Fire Emblem with Intelligent Systems, yet IS mostly charts the course of FE seperately from Nintendo at large...as if they owned the IP (which is often where alot of confusion comes from).
Are you just really making a thread to say that Sony manages it's own partner studios "better" than Nintendo? This is because words in your last post basically are pointing at this direction. Sounds like a unwarranted of concern to me. The "partner" studios of Sony are less "partners" and more directly-owned business units by Sony, and their employees are Sony employees. These studios are obliged to work only on Sony published projects, and in this aspect Nintendo's directly owned workforce/studios (EPD always, NLG now) and Sony's directly owned studios are the same (Guerilla, ND etc).
The "legal ownership" relationship between entities such as IS and GF with Nintendo is much less formal and to my knowledge don't even involve outright ownership. As such they are more like From, Mediavision and Crispy's for Sony in Japan during the PS1-PS3 era. How many of these folks are still working exclusively with Sony?