My dream career is kidney dialysis, I am having a hard time finding a good trade school in san antonio tx?

Be a nurse. It is best to be a nurse whether a 2 years or 4 years degree since you will have better pay than a tech and can change your career from dialysis to other e.g. Cardiology, icu, ccu, etc whenever you want. It is certainly a more rewarding and growing career. Once a nurse, dialysis companies will train you. Seek sites like fresenius or davita for poss dialysis tech training.
Find a dialysis unit. Dialysis companies employ different types of skilled professionals. Some of them are nurses but there are many jobs that the dialysis company trains such as dialysis technicians. Most dialysis companies have education assistance programs to help employees improve their skills. In addition there are many non professional positions in dialysis. Call a unit, get that job.