Ogryn are way too big for a marine to pass as one imo, the size isn't even close, plus the wonky proportions of an ogryn which a marine doesn't have. An ogryn's head is almost the size of a marine's torso kind of difference, they have short legs, long arms and often tusks or partially ossified head growths. Marines are basically human but wide and tall, ogryn are literally ogres rather than being humans but even wider and taller.
Marines do pass for things like Goliaths and other genetically/chemically altered labourers and soldiers. You might even be able to pass off the black carapace interface ports for the similar ports used by other humans in the setting. Short marines can even pass as just normal humans. Marines are weirdly bulky, but a lot of them are under 7" and within the nominal range of baseline humanity.
Obviously marines have gotten taller and wider over the years, as they got flanderised into being bigger and bigger for some reason, but ogryn are still much bigger.
do you think there's a chaos god of cheese, or would that just be nurgle by way of fermentation and decay and whatnot? Individual ones for each type of cheese, for some kind of chaos cheese pantheon?
Cheese for the cheese gods, mozz for the mozz thrones
let the galaxy brie
Jokes aside, no, it's not the sort of thing chaos gods embody. Cheese would arguably fall under Slaanesh as a food item with associations of decadence more than Nurgle, but really no individual food types are linked to them. There's no emotional weight to making cheese and it's not representative of the inevitable slide into entropy.