How to upload image with a url in the path

I have a file which I am need to get from a subdomain eg, images.thesite.com
With he upload it is done under the domain eg, staff.thesite.com
The website is running under the main domain eg. thesite.com

The domain staff.thesite.com is locked to only be allowed from a certain IP address, which is why I need to keep this seperate.
However when I add the https://images.thesite.com/public/assets/images to the file upload then it fails with an incorrect path.

Is there anyway around this to get it to work?