My monstergram says I have a monster (Komocat) but I can't find it anywhere. Would it show up in the monstergram if I had it and got rid of it?

@Helene-Roberts yes. If you ever had it, it will be in your Monstagram. If you tap on the monster in Monstagram it brings up the monster's description. Along the top bar, if you still have it anywhere (even storage), there will be a magnifying glass icon. Tapping on it takes you to the monster. No magnifying glass means you sold it sometime.