Yeah, the little foxes are canines. Dark wolves set necro taming required on canines to 0. So if you have no taming it still may take more than one try.
Summon your dark wolf and go use the taming skill on the kitsune. As long as you have the dark wolf out, you can control the foxes. Just as soon as it's gone, you'll loose control. DO NOT COMMAND IT! Summon up another dark wolf, then you can command it again.
Yes, to have two kitsune out as a necro, you will have to be on foot.
Kitsune are not angerable (they are agressive, use invis), and most tamers can tame them quickly. So there wasn't a big stink over them and necros. (The necro's snake used to let you command yamadons and Serando, hehe, that was much fun to lead around by the nose).
When the cu sidhe where tamable by necros, it was a huge advantage to have the anger cycle removed and be able to tame them on the first or second try. It was almost impossible for a tamer to tame a cu sidhe cause the necros would go out and steal them out from under them while the tamer fought the anger cycle. Cu sidhe where described as fey dogs (and they are in myth) in the ML literature. They where never ment to be canine.
An interesting note is that the dark wolf doesn't let you tame hell hounds.