Can an edited photo on my iPhone be recovered if the original has been deleted?

Just for the photography part: If someone has your cloud storage login credentials and physical access to your phone and changed your photos there, you basically have limited means of recovering the photos.

• If you have a backup of your phone data that is from prior of the event, you may have the photos in there
• If your photo cloud provider has the ability to store versions of files, you might be able to roll them back there. Apple iCloud does not provide this for photos as far as I know.

This means, usually there is no chance to roll back a file if it has been written over the old version.

Apart from that, the situation is more of a legal case. Breaking into someone else's accounts is probably no little offense. You should get yourself a lawyer.

On my iPhone in the Photos app you can revert to the original picture at any time. Select the picture you suspect has been edited, select “Edit”. If the picture has been edited, you will see “Revert” in the lower right corner of the screen. Touch that and it will ask if you want to “Revert to Original”.

You answered your own question. The cloud has your files. However, this is not a photography question and we have no way of knowing if you are the owner of said camera. You could be the person who is trying to access someone else's pics. I suggest we remove this question.