Long-time lurker here, now considered signing up here after reading the news this morning and researching it.
I have a theory about all this, but it unfortunately further implies that the Flog-emulator simply cannot be called through normal means and without additional software (as in, official software from Nintendo that triggers this). I do believe OP has seen what he claims to have seen, but I don't think it required any input from his side. Instead, he might have unintentionally manipulated the hardware, likely by over-heating the console. At least this is how people explain strange occurances in Switch-games like these that don't just create visual glitches but also affect all aspects of the games:
And similar things have been seen in Breath of the Wild as well, likely from the same causes.
(See 4:02)
What seems to happen is that games (and probably software in general) starts loading data from the "wrong" areas and adresses, probably because the over-heated RAM isn't working as it's supposed to. I'm not gonna pretend I know too much about these things, but I do think I understand that much and find it a likely theory. Given this, I could imagine that the Switch tried to boot the Home Menu, but erred on picking the right adress, and booted up the Flog-emulator instead.
Now, if the Switch of OP was just standing by in the Home Menu or any other menu in the OS, it seems a bit unlikely that the console would work itself up so much that it would generate enough heat to affect the internal hardware, but maybe OP played something else for a long time, then switched over to the Home Menu immediately, and THAT lingering heat did the magic, even as he was away? I could imagine that the console panicked from too much heat, shut down and then booted up again immediately, only this time accidentally calling upon the Flog-emulator instead of the Home Menu.
It's a bit of a stretch, but it doesn't seem wholly unlikely, does it?
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The other thing I was considering - if we are to assume that there IS a way to boot up the Flog-emulator properly, as an easter egg - is if there's something about the original 'Golf' from 1984 that could lead us to the emulator. We established that the Konami-code doesn't work, but maybe there's a cheat-code or special input, or special number, or special name in the credits, that somehow can be used as an input in the Home Menu and that loads up the emulator?
I didn't find anything yet, but if I were to look further, I would go with the Famicom-version. It wouldn't be the first time that a modern console references the Famicom:
I just really want someone to figure this out :V
