I've run around my all-but-completed worlds with the map badge on, until every map said there were no relics nearby. I somehow found a fourth cow in Subcon Well, despite having already built the UFO thing, but i still seem to be 2 rift tokens short of getting the last item from the slot machine.
has anyone else managed to get absolutely everything?

I also got the impression that the badge did not point to all tokens, and it did lead me to a repeated cow relic.

I think the devs have stated that there are not enough tokens in the game to get every unlockable. You need to obtain additional tokens from mods. Not sure how that is going to work here in GOG, though.

We're probably going to have to wait for a trainer that has an infinite tokens option.

Enable console and enter Enablecheats

(necessary to use the commands)

then use Summon HatinTimeGameContent.Hat_Collectible_RouletteToken