Criollo ruin 4,5 jaar

I am offering my 4.5-year-old Criollo gelding Amigo (approximately 1.50m) for sale. He has not been ridden yet, as I wanted him to grow a bit more first. Here is my, or rather our, story. I once had my dream horse, a Criollo from Argentina. Of course, he was raised with care. I had to have him put down, and after a while, I went for another Criollo. This time, a 3-year-old who came from Germany and was still green. I had no further experience with young horses. I have underestimated this significantly. I have now tried for 1.5 years to find the right connection, but it is not there. I find him too exciting, and he needs someone who can clearly indicate what is going to happen. Someone who can train him and who is not easily impressed. Not a dominant person, but assertive and with heart/honesty. If he finds such a person, he will become a dream horse. But I cannot offer him this; I do not have the knowledge for it.