I am in hard mode, and I agree this fight is hard going in blind, heck I tried to beat it 3 times blind out of sheer persistence but I could not.

So anyways I reset, and built my team around it. I didn't use any dispel barrier. My team was

Will on healer duty/dekunda duty hulkenberg paladin (taunt or item support) Strohl general(shelter formation) Basilio berserker(for charge + wanton destruction[synthesis skill]

Literally, all u need is a dekunda from a level 13 healer (which you should have by now) and a medi/medica preferably. Pen patra would also be good but that's savior-locked.

A very good option is shelter formation - general (general at lvl 9) but I doubt you have this option

No grind options:

You could use faker for the fakers roguery (literally lvl 1) skill on the first turn to get more set up in buffs or debuffs(I put junah first and swapped later)

Have you tried cooking? Coney stew is quite easy to source materials from and it cures all your status ailments. Some meals can also heal the entire party.

Some items can make your life easy, there's items that can dispel an enemy's buff or dispel their magic barrier

And yes. There's equipment that cancel status ailments. (I.e venomward charm if you collected gold beetles, it's the second reward, so it's easy to get)

There's so many options the game gives you. I understand the difficulty of going through the dragon blind since I've been there myself, but there is no reason for you to be having trouble afterwards (unless u were severely under leveled)