My integration of a couple of bantams in a standard flock in December didn't go well at all. I will try to sum up the few lessons that maybe could be of use to you.
There are three moments when things can get bad : roosting, feeding, and laying. For when you will be absent, you want to try to make sure Kraai can do all of the three without getting trapped and taking bad pecking. This could mean having two different food stations, and waterer. If you get a chance to see what happens when Kraai lays, you can also adapt and maybe add a nest box. But if she is like Chipie she will try to lay with the other girls even though this means getting attacked.
I believe if you stop putting her in the small coop she may try to join the rest of the flock for roosting. I would maybe give it a try before leaving for vacation, because if I've understood correctly, your neighbour won't be putting her to sleep and won't see what happens.
What did help with my integration was the fact that the newcomers had several places to shelter. Just one place (Kraai's run) may not be enough, as what happened to us was that the older standard hens trapped the bantams in their run by staying in front of the entrance and blocking them. Luckily the bantams could fly better and flew over the entrance of the run into the big coop. Also they found themselves several shelters inside the big coop quite high where the other girls left them in peace.
Although it's too much to ask your neighbour's to watch the chicken's behavior, they can maybe check that Kraai isn't hurt, bleeding in the face, especially in the first days.
Kraai is lovely and it seems the fact that she is the same size more or less as your other chickens helps her with integration. I think it's a good sign that she's standing her ground with some of your chickens, it means she is not too afraid and won't be too badly bullied!
There are three moments when things can get bad : roosting, feeding, and laying. For when you will be absent, you want to try to make sure Kraai can do all of the three without getting trapped and taking bad pecking. This could mean having two different food stations, and waterer. If you get a chance to see what happens when Kraai lays, you can also adapt and maybe add a nest box. But if she is like Chipie she will try to lay with the other girls even though this means getting attacked.
I believe if you stop putting her in the small coop she may try to join the rest of the flock for roosting. I would maybe give it a try before leaving for vacation, because if I've understood correctly, your neighbour won't be putting her to sleep and won't see what happens.
What did help with my integration was the fact that the newcomers had several places to shelter. Just one place (Kraai's run) may not be enough, as what happened to us was that the older standard hens trapped the bantams in their run by staying in front of the entrance and blocking them. Luckily the bantams could fly better and flew over the entrance of the run into the big coop. Also they found themselves several shelters inside the big coop quite high where the other girls left them in peace.
Although it's too much to ask your neighbour's to watch the chicken's behavior, they can maybe check that Kraai isn't hurt, bleeding in the face, especially in the first days.
Kraai is lovely and it seems the fact that she is the same size more or less as your other chickens helps her with integration. I think it's a good sign that she's standing her ground with some of your chickens, it means she is not too afraid and won't be too badly bullied!
But the coop is not far from our bedroom. So I probably wake up if they start to fight tomorrow morning.
?
I’m confident that it will be okay to leave the ‘gate’ between the runs open when we leave on Sunday. 
Today I cleaned both coops and nesting boxes. So they should be fine for a few weeks with enough food and clean water. 
I do ask the neighbour to refill water and feed in several places to avoid quarrelling.
