So, In the query filter, you should use "meta_type=NUMBER" instead of "meta_type=DATE". This will solve the sorting issues if they appear. Screenshot; Screenshot 2021-04-03 at 16.03.20.png
Regarding the display of the date, you need to check with the Oxygen support team how to format a timestamp into a date string, or you need to use Types shortcodes instead of the "oxygen shortcode".
Problem:
Custom Field Group not showing with ALL conditions met option
Solution:
If you are trying to add/Edit post - as you know with new post until and unless you save/publish the post there will be no term value assigned to that post.
Please try to save/publish your post and see if you can see the custom field group.