Ah, yeah I didn't even think to look there. I can confirm I do have them in my pack. It's my personal opinion that for ease of use I'd include at least two frames (fully open and fully shut), since there are situations where using the animated prop doesn't make sense, so you don't want to import and spend time filling metadata for a whole other sprite sheet to only use one or two things.
But I would consider it fine as is, my bad for not seeing those. It's worth saying I'm not an RPG maker guy, so my perspective is that of Unity + Godot users.