Trouble in Paradise

Obviously in this job, we are not going to agree on everything. Most of the time, I just shrug it off and do things their way because nothing has been a big deal. Camila is growing into a well-behaved, well-rounded child, so I guess we're doing all right. But right now we are having the biggest disagreement I think we have ever had.
She is going to a Mom's Day Out program two days a week this fall. That means for 8 hours of the week, she will be with people we don't know and children we don't know, in situations she has never been in before. She will be doing arts and crafts and making friends and playing outside, I know. But we do that together.
Obviously, I am not really for this idea. When her mom signed her up, she was pregnant and freaking out about how we would make it with two such young children. I figured a back up plan would ease her mind and let her do it, assuming she wouldn't really go through with it once A) she saw how well we could handle two, and B) she realized how young Camila really is. She is potty trained, yes, but she isn't even two yet!
Her mom is still determined to go through with it, even though she is nervous and not sure it is the right thing to do either. She is getting frustrated that I am not coaching her through like I do most things (for example, potty training!). I finally had to confess to her how I was feeling and why I hadn't spoken up before. She was surprised at first, I think, but then interpreted it as Camila is just still my baby and I can't stand the thought of her growing up. But she now isn't expecting my support as much, so I will say open communication is the best route to take.
It's just that kids change a lot between two and three. She is going to be facing changing behaviors in other kids and won't know how to handle them. When we are with her, we can tell her the right way to react the first time. For instance she was playing with an older girl that had a toy she wanted. I could tell she wanted the toy, but wouldn't do anything about it. I finally asked her about it and suggested she ask the girl if she could have a turn with it, because I could tell the other girl didn't care that much, she just didn't know that she wanted it. Camila walked up to her and said, "My turn, please?" The girl gave her the toy and everyone was happy.
When she is by herself, she doesn't know what to do. She may get frustrated and just try to grab it away, not knowing what else to do, and then she will get in trouble for it. (As she should, because she needs to know that's not right.) If a child is picking on her, I'm afraid she'll have had enough and bite them for it. When she is four or even three, we can tell her at home, "When so-and-so does this, go tell a teacher, etc.". At two, she can't think ahead and later remember things like that. She only knows here and now.
And when she sees other kids misbehaving, I tell her "That's ugly, huh? We don't do that because we're going to be nice." At school she will not have that interference run and may decide some of this stuff would be cool to try! She is only a baby!
I also don't think she's ready mentally and emotionally. We've worked for almost two years on a trust basis, of how she could try anything because we would be right there with her. Now we're going to just dump her off with strangers? (In daycare, the 2 year old rooms were the absolute worst rooms to have new kids because they had no clue what was going on.) She won't use the potty anywhere but home, so who knows how the potty training thing is going to go there. (She's completely trained now; even in public, if she has to go, she holds it till we get home.)
It's one of those situations where I have done so much "co-parenting" that it's frustrating that no one is listening to me. They insist if she hates it they'll pull her out after a few weeks and try again later. (I still maintain she might love it, but pick up a lot of bad behaviors that we can better avoid when she is older.) For her sake, I hope she doesn't hate it, but I also want to be right. Isn't that terrible? But one more thing...Mom's Day Out was designed for poor frazzled mothers that want a couple hours for doctor's appointments and grocery shopping, not children with nannies that don't want a break from the child anyway. If we pull out, someone that really needs the spot may get it. Sooooo it's not totally selfish, right?
If anyone has anything to say that might make me feel better, I am ready to listen!