Can anyone tell me what the likely issue is?

It listened to where the whining noise is and it appears to come from under the engine bay cover - and there seems to be something that is disconnected (circled in red)

https://photos.app.goo.gl/DcdTAH8LzcWS3sFB7

I'm looking to find out whether its still OK to drive before I book it in to be fixed!

 

Is your power steering low? You should be able to easily pinpoint the noise with an automotive stethoscope - or a long screwdriver held to your ear to feel the vibrations. Make sure you don't have a bad bearing related to your timing belt.