The nature of the work is not as relevant as you think. I am a hiring manager. And any professional reference is good if you can't have the very best. So like any co-worker, whether it's from when you were teaching or another position is fine. The things we're going to ask your reference are about your work ethic and punctuality, not necessarily about details of the job or the actual tasks you will have to do. Obviously a person you reported to is better, but failing that, a coworker does just fine. I have been hired for promotions using people on the same level as me. A personal reference can be a professional reference.

I think some responders here (not you Streetcar) are confusing what a professional reference is. It's not the HR manager at your previous job who is only allowed to confirm employment, position, and dates. I can call ALL your past employers and ask them to confirm employment. The professional references are people you have given permission to speak to your professionalism. So a professor or coworker can work just fine for this if they're willing to say the positive things about you like you turn work in on time, you show up on time, you work hard, go the extra mile. References are a bit of a formality. Employers don't expect to get anything particularly telling out of them. It's mostly due diligence.