I understand that "life happens" and gets in the way of plans, but I am wondering why you have a horse that cannot be touched, and seem (so far) to not have any interest in training it? Sounds like a big liability since the horse sounds like it is dangerous.
Either your farrier must charge you an arm and a leg for his services, or he's a glutton for punishment. NO FARRIER should have to trim the feet of a horse that can't even be haltered, because I would imagine they won't hold their feet nicely. It's a little bit different of a scenario if you are dealing with (for example) a wild mustang that was just adopted and is in need of serious hoof care. Not when a horse just keeps their halter on all the time because the horse is head shy ..... rather than fixing the head shy and violet problems.
Sorry for the rant, but if you've never taken the time to work with this horse, you aren't going to get her halter back on today. Or tomorrow. Or maybe even the next week. Training takes time.
Treats are fine and dandy, but what are you going to do when the horse isn't interested in a treat? You've got to demand respect from the horse whether or not a treat is involved.
Get yourself a trainer (probably a different one since it doesn't sound like this guy did much, nor are you a fan of his methods). In the meantime, you can look Clinton Anderson or Chris Cox. They've both had episodes of dealing with hard to catch horses. Basically, always make the horse look at you. If the horse is not looking at you, then you are making them work. Once they look at you, leave them alone. This teaches them to pay attention to you and respect you as the leader. Also, don't square your shoulders directly at the horse. That's confrontational. Always have a slight angle in your shoulders away from the horse. Don't try to "sneak closer" to your horse. That's acting like a predator. Walk up casually and normally. Do NOT try to touch the horse, until they are ready. Most people try to quickly grab to catch them; that's setting you back. When you actually go to touch the horse, it should be a comfort to them that the leader is touching them. The horse should literally be following you around as the leader before you even try to put the halter on. When you do put it on, be careful you aren't pulling on the ears or hitting them in the eyes; that's not comfortable.
I have never once left a halter on a horse. It creates rub marks on their face, and is just waiting to get caught on a fence.
∞*˚ Βгįťţαňγ ˚*∞
It is not enough to know how to ride; one must know how to fall.