Change Apple ID over to mine

We have a work iPad Air which was set up by a colleague in our head office a few years ago, he set it up using his work email and a password, which we all were given.

In general all iPads were used for an app called Traction Guest which is a sign-in system for our reception team to allow visitors to our building to sign in via the app.

We have gone under huge renovations over the last year and a half and the iPad has been sitting in a box in my office, I'm trying to back it up but it's not accepting my password.

The person who set it up has long left the company and his email is no longer active so we can't reset the password.

Is there anything I can do to change the Apple ID over to mine?

​[Re-Titled by Moderator]