accessing iPhone without using the screen

My iPhone 6S+ is afflicted with the (apparently common) digitiser malfunction. It is almost impossible to use the phone for any specific function because it will automatically click everywhere as soon as the screen is enabled.

I have a MacBook air on the same account, but I have thus far been unable to navigate the trust alert due to the screen issue.

I have also attempted to use Switch Control which works, but since this still turns on the screen the same issue occurs with that and it is uncontrollable.

I want to re-authenticate my WhatsApp number on the device so that I might retrieve my messages which haven't been backed up since March.

I also want to access my photos and other data which haven't yet synched due to my icloud being full. I have now cleared space in the cloud, yet for some reason the phone still hasn't synched the current backlog (perhaps it's too busy flipping out, I don't know why...).

Are there any other ways that I can access the files or device without needing to enable the touch screen? The finger print scanner and home button work, and I also have an iPad if that helps. Perhaps some online accessibility is there, or some solution using apple script exists? I have no problem using developer-friendly solutions if there are any.

Thanks very much in advance for any help