If you've never played your other classes past lvl 7, chances are your monk heroes have really bad builds (the skills they get as default aren't the best, unfortunately - I struggled with this a lot on my second account before I got some decent skills unlocked), so you'll do better with healer henchmen keeping you alive for the time being. Even with a good build I'd still only take one hero healer out with you and use the other two hero slots for good damage dealers or midliners such as an interrupt ranger or mesmer or an MM which you can't get from the henchmen. In Nightfall I usually go with Devona, Sogolon, Herta and Mhenlo as my four hench, regardless of the class I'm playing.
Try going back to the Sun Docks and talking to the NPCs in there - you might find you get either Sousuke or Jin as a hero when you get your quest reward. Alternatively you might still have the quest to complete - do you remember defeating Balthazar's Eternal and a couple of ghostly griffons outside the Astralarium? If not you need to go do that. (Might have a few names wrong there, too late for me to be bothered to go check it out.

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To get MOX to go attack before you do you need to pick a target and click Crtl-Shift-Space, wait for him to run in and take the initial aggro, then hit space again to join in yourself. Alternatively stick him on attack and he'll go attack anything in your aggro bubble and then some.
For armour, crafting and armour collectors are the only way. Crafting gives you a better choice of appearance and means you don't have to farm the collectable drops required (can't remember what or where the max armour collectors are in Nightfall off the top of my head, you'll need to wiki that or get someone else to post it for you), but it means you have to have the mats for it instead as you discovered. Best way to get the mats is by expert salvaging armour drops (rags, harnesses, hides, etc) with an armour over 20 (normal salvage it if under 20, you won't get many mats and only very rarely a rare mat from it) and any blue items that ID as highly salvageable. You should find you have over a stack each of cloth bone tanned hide and iron ingots in no time if you do that. Max armour for a dervish is 70, by the way.