If you knew that your daughter had problem with nuts, then yeah... you should donate it. But nuts aren't a big factor in reflux or eczema -- believe me, I've done obsessive research since one of my daughters has severe reflux -- so I'd keep it and use it. If you want to do a trial with no nuts, leave your frozen milk in the freezer for a month while you nurse your daughter with "new" milk. Then if you see a major difference, you may decide to donate your old milk. But if you don't see a difference in her conditions you can go back to using the frozen milk.
All that said, are you doing other things for the reflux and eczema? Make sure you're keeping your daughter upright for at least 30 minutes after each feeding. Have her sleep on an incline at all times. If that means she sleeps in a bouncy chair, that's ok. But not her carseat... that position actually puts pressure on a baby's stomach and causes extra reflux.
You also mention a poor latch. Are you supplementing with formula? If yes, make sure it's a hypoallergenic dairy and soy free formula like Nutramigen or Allimentum. If you're supplementing with formula, she's getting dairy through that and all your efforts to cut out nuts and dairy wouldn't matter.
Whatever you decide, don't throw the milk out yet. Make sure that your daughter truly has a sensitivity to nuts (which is really really rare in babies!!!) before you dump the milk. If you have any specific questions about reflux, feel free to PM me.