If there's no contact you got no legal recourse. I'd level with her.
"Look, you missed two deadlines. Give me another one but give me a real deadline you're comfortable with, not one you think I want to hear. I just want my photos and you're I see you're busy so let's agree on a date and time you can deliver these photos to me."
Then it's on her if she doesn't deliver instead of you feeling like an ass for pestering her. It's on her for the previous missed deadlines but look at this kind of conversation as a restart. Nothing before matters.