I am convinced that it takes 4 full years to potty train a Yorkie. I have only owned Yorkies and have a 6.5 month old, too. Jesse has his accidents and wants to mark everything from the blankets, to the walls, to the base of the toilet. In reponse to your situation, the crate has to be large enough for them to turn around in and NO LARGER. This is your only hope. The dog is let out to eat and then taken directly outside approximately 30 minutes after eating. If she doesn't poop, so be it....it's back in the crate. The reinforcement part of it is crucial...praise and reward. When you are taking her outside, come up with a few word statement, such as "outside for pee pee", or "let's go do pee pee." My female is 4-years-old and pees and poops on command. She was pad trained, as well, but used to face the pad, front paws on the pad, and then proceed to pee and poop off the side into the carpet. There is no credit for being close....
It is so frustrating, and we all feel your pain. I can assure you with great sincerity, however, that the positives well outweigh the negatives. They are so wonderful when they are trained properly....All the best, Lisa