Is There a Reason Why Dragoons Cannot Roll on Scale Armor?

Not sure if SE said anything about this or maybe it's just a bug, but I noticed tonight on my DRG I could not roll need on scale armor. Even though scale armor is basically meant for DRGs, since it's less defense than plate and more defense than leather with basically the same stats.
It says on the armor that it's useable by LNC and DRG obviously, but only the tank could need on it. Of course he did, then he also proceeded to need on the plate that dropped for the same slots and got those also.
It wouldn't be a huge deal, but if DRGs can't roll on scale, then we can only roll on leather, which then takes away from Monks and Bards. It just seems silly to give Tanks first dibs on two sets of armor when one is just inferior to them.

If you are saying that a DRG couldn't roll need for an item that has the LNC/DRG description then that must be a bug, I suggest you to fill a report but with the amount of problems that they already have you should wait a bit to do so...

You should fill out a bug report regardless of the server problems. Those are hardware related and are probably not affecting the development team tremendously (the operations team has to deal with that). Bugs should be reported as normal.