No I would not let him do it in his own time in this case because I think he is too timid to come out for treats and he may end up biting you due to fear. We have tamed hundreds of hamsters and you can gauge what they need. He needs intense taming and almost forced handing in my opinion. It won't take long
I took some pictures of this little one who came to us very scared and biting. I warn you it does end very sadly but she left her legacy in that she became tame and the pictures sort of show the process.
Sparkle's last chance