I'd say he's not interested in rehiring you.
If he was, he'd have jumped at the chance to rehire you.
I'D send a nice thank you note for his time, a d remind him of your proposal. If you don't hear back, he's not interested. Open door or not.
He may feel you left, and are coming crawling back, not an attractive attribute.
Or, the proposal you have doesn't fit his requirements.
That's just my take.
Good luck.