I think I would take anything she said with a horse-sized block of salt, because she clearly knows little about what she's doing and apparently doesn't care.
Your black doe's body profile could be "semi-arch" (she's not posed, so that may not actually be the case) and she does have good large ears, but that picture doesn't shout "Flemish Giant" at me - her head, especially, just doesn't get me there. She probably has a healthy dollop of Flemish in her, but I think "Flemish mix" is about as far as one can truthfully go, and that's a guess (that baby with the white on it is hers, sired by her brother, correct? That's Dutch marking, which shouldn't ever be seen in purebred Flemish).