As already posted -- your horse is in serious need of a good farrier/trimmer. I'm glad that you are searching out another one, since the first one you called gave a response that doesn't make any sense. You want the frog to touch the ground. And unless your son did a professional's job on the "first aid" trim job he did, those hooves would still need attention by a pro.
Please let us know when you find a new farrier and have a care plan. This is going to take quite a while to get straightened out, so be patient. In the meantime, read up on hoof care (Pete Ramey was already mentioned I believe) and ask your new farrier to explain what (s)he's doing and why. The more you learn, the more questions you will be able to ask.
I would not be riding this horse until a farrier OKs it.
How is the rest of his physic?