First solution as I said, if you replace:
/category1 [order 4]
With:
/category1/*$ [order 4]
The new article doesn't take the meta tag of category1 just because its URL doesn't match with /category1/*$ (and if you understand regexp you know why).
Second thing. In tag meta you can order your entries and they are scanned in the order you choose, so that just the first one that match URL is applied. So you have another possibility, for example, to move your new article just before /category1.
Finally, I saw your review and your low rating on JED. I think everyone can think as they like, but is not correct to judge before having an answer. So despite this answer is good or not for you, please, forget Tag Meta. I'm sure you will find a better component for your specific needs.
Regards,
Luigi