Thanks for picking this up! It's an interesting series that hadn't gotten an update in some time.
Overall good quality translation. One thing though, the sentence " My past experience in handling children in yancha is being useful" or something like that) is wrong
yancha is the word used to describe naughty or rascal children. So a better way to translate it would be something lik e"My past experience in dealing with naughty children is of some use"