It sounds like a tough problem that you are not going to resolve before you leave.
First realise that there won't be a lot to do when you get back. They are not that quick as you say.
Second discuss with the team the problem: If you need to correct all their work when you get back the project will get delayed and hell will be paid/management will be displeased (depending on management culture). So you expect them to do minimale code changes and spend extra time testing. In your absence review each others code changes so you won't have to spend too much time approving when you get back. Empower them.
Third, but long term: If you are the most competent person in the room look for another.
First realise that there won't be a lot to do when you get back. They are not that quick as you say.
Second discuss with the team the problem: If you need to correct all their work when you get back the project will get delayed and hell will be paid/management will be displeased (depending on management culture). So you expect them to do minimale code changes and spend extra time testing. In your absence review each others code changes so you won't have to spend too much time approving when you get back. Empower them.
Third, but long term: If you are the most competent person in the room look for another.