Former employee's iPad reset
There is a nice set of procedures to follow:


Can&#39;t log out of someone else&#39;s find my iphone without their icloud password


If you can go to the settings app and erase all content and settings, you don't need to mess with Activation Lock or contacting Apple or the employee. If not, then you can start with the linked question for a playbook to solve your dilemma.

Here are the options to bypass Activation Lock:


How can I bypass Activation Lock?


In your case, your Apple Sadler rep or service organization will need to verify that it is a company owned device unless you have an MDM that uses device enrollment program (Apple DEP).