the two woman have in the MonsterVerse - series "Monarch - Legacy of Monsters", - supported by a greater couple of technique stuff, also to record the sound pulses from the alpha protagonists I don`t know, what cassette deck is used - never seen a three-head-deck like this, and you can have a closer look to the earphones to check.
I guess no... nevertheless - i like this toploader design, - as written at youtube, it`s one of the last built toploaders, so the monitoring function ( and I only know of this one effect for which the three heads would be useful ) is good developed at this time in the middle 70-s.
It looks like a sleeper I suppose it's a good performer , it has also Dolby , for this year of manufacture I'm not sure if it uses any IC for it or it has a pcb with discreet components , top loaders were the norm at the early to mid 70s so we should expect top models in this category even more so if this Sanyo is one of the last of its kind. Indeed the three head configuration makes perfect sense for monitoring. Nice catch!