DraconiumOre cannot be harvested by the Builder because it always returns false for canEntityHarvest. I'm not sure if this is a bug in RFTools for checking this method or in DraconicEvolution for returning false.

Enable harvesting of tile entities in the rftools config. This is disabled by default for safety reasons.

I have it enabled, still doesn't work. Actually, I meant canEntityDestroy, not canEntityHarvest

Hmm. No clue. In any case, RFTools must call that method. That cannot be prevented. Not sure why it would return false though.

It's hardcoded that way, not sure why though:

https://github.com/brandon3055/Draconic-Evolution/blob/master/src/main/java/com/brandon3055/draconicevolution/common/blocks/DraconiumOre.java#L39

Actually, I now know why, to prevent the dragon destroying the ore:
Draconic-Inc/Draconic-Evolution@b0b063b

I guess it is a bug in DE.