Here's the info on resetting the root password:
https://www.linode.com/docs/platform/ac ... t-passwordThis will give you the ability to log in as the root user over SSH, or LISH if SSH has been disabled for the root user. Please note that it requires rebooting the Linode, which = downtime.
As for how you want to get your files from there, that's really a case-by-case answer. In any case, I'd suggest you pursue other avenues of communication with your developers before you start rebooting and changing passwords.