Mind I started playing this map again recently just on local but they typically spawn for me on the snow mountain south of green ob (where the managarmr cave is) and sometimes at the top of the mountain north of that. So far I haven't found any by blue ob. The Dino Scanner on S+ Tek Transmitter only ever shows one.

Seem to be rare only one seen in 4 weeks so far, it was only 50ish but I still had to grab him.

As I noted in a different thread, fwiw, OIympus seems prone to the (relatively common in ARK) issue where common spawns crowd the population table and leave no space for the rare spawns to happen. Doing a destroywilddinos every couple of days seems to help the rare stuff (gacha, snow owls, etc.) show up more often on my map.

We've been on Olympus two weeks now, and with a destroywilddinos every few days we've managed to snag three gacha and two snow owls. So while they aren't frequent, they can show up more often if you periodically blow away the wild dino table.