Exactly what I was going to say Playfelt! A video monitor with 2 way voice. I have one and I don't know what I ever did without it. It cost me about $200 and it does 4 cameras, that's $50 bucks a sleep area and well worth it. There is nothing funnier then when you give that command through the monitor and they don't know where it came from. They flatten like pancakes. lol

Aside from that, when I have a child crib jumping I spend a few days with the crib on the main level. I'm able to put the child back in the crib as soon as they try to get out. I have a daycare room that can be closed off for napping. This is how I train my new ones to sleep here as well. Once they get the hang of it then they move back upstairs. It screws up my quiet time for a few days, but I know it's only a few days and I prepare to have my quiet time screwed up, so I'm ready for it.

In regards to the crying child. I'd just deal with the crying. Continue to let him know that he's ok and if he'd like to come play he can, if he wants to sit and cry then that's his choice. I would sit close to comfort but rarely pick up. They need to learn that this is the way things are done at your house. Give it a few weeks and if he still isn't getting the point I might consider terminating just because it doesn't seem that he's doing well with you. Maybe not a good fit.

I hate crying children, but sometimes you just have to have a lot of patience and push through it. It's their only way to communicate. We just need to teach them other ways.