I really think your best bet to get Maggie started is to leave Smokey inside. If you could work with her 1-2 times/day for 5-10 minutes, she would start to lean the commands reliably on her own. Maybe if you give Smokey a PB filled kong, or other yummy treat, he won't miss you as much for those few minutes.

Once Maggie is fairly confident in the basics, then you can work with the two together.

When we were training Cincy, I would take Sadie in one room and work with her, while Ralph worked Cincy in the other room. Then we would switch, so they both learned to listen to both of us. It was more of a refresher for Sadie, but I think it helped Cincy focus to be on her own while she was learning.