Admittedly I'm not 100% sure on the dev process of games, but afaik its more along the lines of the developers make the games, using special development versions of the console in question, which are then sent of to be put on disc, somewhere along that time Sony "sign" the code so that it's official.
Thb I'm not sure, but as far as I'm aware there aren't any secret emulators used by devs, there is one but I cant remember the name of it, and it was for SNES games I believe. Like I said I don't know 100%, so anyone feel free to correct me.
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