I went through several submissions on SS over a few months and it was frustrating. I believe that those other 7 images are reviewed so are likely to be accepted, but is not clear in the rejection email.
How to get approved in your situation? Well there is no right answer as it will depend on who is reviewing your 10 images.
Submitting 10 new images is a good plan. In the worst case scenario that you are rejected again you will hopefully have a total of 10 images that have not been rejected and you can submit them. If you are rejected the following attempt I would suggest that you submit an email to SS and they will review the situation. I did this and they reset my account so I could submit 10 images that had not been rejected in previous batches and I was finally accepted - lots of effort by worthwhile.
i reapplied today (second attempt), used the same images that had not been rejected and added a few new ones. i did go back and reduce the size of the images that had not been rejected to just over 4 mpix, just to be sure. i made sure all the images were shot at ISO 200 or less. We will see how it goes.
