If ALL your other orders are in batches, and orders are only in one batch each, and you have not removed them from those batches, an option would be to go back through all recent batches, apply a tag (eg 'IN_BATCH' or something) to all the orders in those batches, then filter by date (make sure you have gone far enough in the batches to go past the date you are filtering by) and search for orders which DO NOT have that tag. Those should be the orders that were in your batch.
Note that from the main page you cannot filter by negative conditions for tags (does NOT have flag) and will have to go 'Saved Filters -> Manage Filters' and create a filter to do that.
