I support the recommendation from others to report this instructor.Well the drysuit itself had no buoyancy since it filled with water. And I used a size small Aqualung bcd (can't remember which type exactly), and they seem to generally have 12-13kg lift.
When I take someone in with a drysuit for the first time its a maximum of 6m with a weight check and inflations and dump drills. I don’t care how experience or not they are.
I've often demonstrated to warm water divers their BC isn't good enough for cold water by fully inflating it then putting their weights on top, most sink. Exactly what would happen underwater.