I like your thought – Henry ran off and Neal and Emma are chasing him.
Neal ‘ran’ from Emma once, I hope he regretted it, and hope he wouldn’t run again.
As far as Regina letting Henry go with Emma, I don’t see that, nor do I see Emma allowing Henry to tag along on such a trip.
If anything, I think it will be a case of Henry stowing away in Emma’s car….wouldn’t be the first time 😉