Does your phone store photos when the camera has been initiated by a third party website or app?

I rented a car last week and we had to scan a QR code which brought up the rental companies website to report damages on the vehicle before leaving the lot. I scanned the QR code and when I selected take a picture the website initiated my phone camera and I took pictures of previous damages. Upon returning I was told by the company that there app doesn't always work and they have no record of those photos. Since it the pictures were taken and uploaded to their site my photo's app does not have them stored. Since it was taken with my phone do these get stored some where hidden, and how can I access them?

Appreciate any help!