I just want to say, that you can teach an old dog new tricks. Honestly, I have an older aging sick dog right now, and I actually just taught him a new trick to keep his mind busy
People that rescue animals often have to start from day one again, as if an older dog is a puppy. So, even though they may bark like mad in the beginning and probably annoy you no end. Start over from day 1 basic potty training. Start to crate train them. Have your rugs cleaned professionally..Put them in the crates and take them outside to do their biz every hour or 2 in the beginning if thats what it takes. It seems like they have decided you are not really that serious about where they go potty, because every time you yell and clean it up, they dont really know what the fuss is all about.
I have a puppy who was trained, but then after surgery got a bladder infection and started having accidents everywhere. I didn't correct her because I was feeling bad that she just had surgery, lol. So, she started getting the idea that mommy doesnt really care where I go. I ended up having to start all over as if she was never trained at all, and lo and behold she remembers the rules. She realizes that much better things happen if mommy is happy....treat for doing her biz outside. Another thing, since they are alone so much, maybe you can take them to a puppy park once a week or something with your boys. Its alot of fun, and the dogs would begin to have something fun to look forward to.
It would be so sad for all of you if you had to give them up a this age. And its much harder for them to get adopted out together. This is exactly the age most of the Yorkies in rescue happen to be.