dunno man I'm with hazuki on this one.
he could have phrased it better but it is true that naoto is too trusting of other people.
plus it's not that Hazuki doesn't trust him, but naoto is an omega and needs to be more wary of other people.. not everyone he meets will be a good guy like the singer dude here.
also, he already knows hazuki is a jealous husband so the least he could do was tell him what happened to diffuse the situation instead of prioritising that other guy over his husband's feelings.