There is no clear definition of what constitutes a moon other than it being a body that orbits another body that orbits the parent star.
There are some astronomers who say the dividing line between a moon-planet/dwarf planet/asteroid system and binary (or more) planet/dwarf planet/asteroid system is whether or not the barycenter of the orbits is within one of the bodies or not.
And fun fact: if that definition gained acceptance, it would mean that the Pluto-Charon system would go from a dwarf planet-moon system to a binary dwarf planet system. Charon could get a promotion.
The article mentions that previously they used pig cadavers with dyes and specially marked tissues to guide the robot. While it doesn’t specify exactly what the “lifelike patient” is, to me the article reads like they’re still using a pig cadaver just without those aids.