How to load images via file open dialog in TestCafe

Background info:

Our application depends on different sets of medical images (due to medical environment we can't share our code). On each image, a set of test cases is run. Each time we need to manually select a new image, which of course we want to automate. The loading of images is fairly complex, but our devs created a button that covers all that. This button opens a File open dialog.

My Question:

How can I open a file dialog window and import new images with TestCafe?

We've tried:

• t.setFilesToUpload (which not seems to work because it needs a selector where the images gets uploaded to?)
• List item clicking the button (it does not open the dialog window)