It's funny -- I was thinking that your last line would probably be what would end up happening -- Curdle would meet Miria again somewhere outside of the city. The only thing I know for sure is that she definitely will not have him leave the city with her. She's already taking enough risk as it is, she has nowhere to hide Curdle (the guards would check her tiny cart), and she barely knows the guy enough to go that much out of her way to help him. Right now, her idea of helping him is letting him go without alerting the guards. 

I don't think there is much he could say that would convince her to help him escape. She may feel a little sorry for him if he tells the truth and if she believes him, but I think it's too soon for her to go the extra mile... unless we really kick ass with the dialogue and they form an instant connection. But I dunno...

Well, in any case, it seems like you've got a plan in place if Curdle is caught, otherwise we'll see how clever he is leaving town. We'll see how it goes! :D