So sorry you had to go through that Ignore the bad talk and just do your thing. If they have useful things to say, listen to them. Otherwise don't pay them attention.
Somehow people are expecting insane gear for HM dungeons even though most are doable with lesser gear ilvls, albeit a tad more challenging, but thats where people go to gear up, so they might as well suck it up.
Compare your rotation to Odett's or others that are posted online and see if there is something to adjust or if they are indeed just pinning blame on you for no real reason.