I'm a bit worried at why there's a loose unfired cartridge that looks like it fell the moment Kalina yanked out the magazine
These malfunctions are actually pretty common (as far as malfunctions go) with AK and they tend to dumbfound a lot of inexperienced AK-only users who believe their gun will never jam and don't have to practice malfunction clearance. It basically is a factor of the magazine (usually lips) and the feed ramp. Basically as the bolt feeds the round the back slips out prematurely causing the whole round to bounce clear of the chamber mouth and the bolt wedges it in the corner of the trunnion. It wedges the bolt open so you don't get any out of battery firings but your hammer drops without doing anything. If you tap rack bang for malfunction 1 clearance which is the first reflex, the real issue isn't fixed and often that set up for a doublefeed when you do finally pull the first round out of the ejection port. Likely that is why there is another round falling out the magwell but the artist may have just added this detail just from observing other stovepipe malfunctions form gun videos or training books where the round tends to hang just out of the magazine causing it to snap out when yous strip the mag out.
M16 isn't immune to this type of error either, but it is a lot less common since the upper receiver serves as a secondary guide to allow loose round to feed into the chamber. With an M16 the round (typically due to case ejection failure since the M16 uses a plunger to eject which can get stuck if dirty as opposed to the receiver blade on an AK) can hop up into the space where the charging handle and gas key run. I think some people call it like "bolt override" or something but it is such a rare malfunction I don't think there is a real name for it. Typically you fix by ejecting magazine, pulling the bolt carrier back using a finger in the ejection port and letting the case drop out the magwell.
I'm a bit worried at why there's a loose unfired cartridge that looks like it fell the moment Kalina yanked out the magazine
It's typical with malfunctions. It could possibly be a double feed where there's a round already in the chamber that didn't eject fully causing a stovepipe malfunction. The bolt being partway forward but not in battery can partially strip a new round from the magazine but not fully chamber it. This means half of the second round is still in the magazine. When clearing this malfunction, you remove the magazine and rack the bolt until it's completely empty. When removing the magazine in this condition, the second round will forcefully drop out of the magazine. This is normal and happens all the time. Given the first round looks unfired, it may have been a dud and Kalina tried to clear it but short-shucked the bolt which would be believable since the first time we've seen her with a gun is in Continuum Turbulence.
