Employees are Hired. Volunteers are:

That’s pretty much the question. I hire employees. What’s it called when I bring a volunteer into my organization to do volunteer work?

Recruited, I’d say.

“Accepted.”

Abused.

Another vote for “Recruited”.

Enlisted.

Recruited, enlisted, accepted.

From the side of the volunteer : I’d say: “joins.”
“I joined the cat shelter as a volunteer today”

From the side of the organization,I’d say: “signed up”, (or “signed on”).
The boss might say :“folks, meet Bob—our new volunteer. I just signed him up today to help out in the cat shelter.”

On the other end, when the volunteer is caught pilfering from the donation box, (s)he is “terminated”?

Employed.

Joined, brought on board, recruited.

I recruit volunteers to work in my program at the city shelter. Once they are recruited I usually just say “have”. In fact, I have two new volunteers who started last Tuesday. Yay. Now we are staffed 7 days a week.

Thankfully I have never had to do this, but I would probably say “dismissed”.

Wow, y’all are nice. I would say “prosecuted.”

“Disappeared.”

In the military you don’t volunteer. You are voluntold.

Retained.

pressed

I’ve heard the term enrolled used.

Abducted, drugged and brainwashed, at which you are no longer a mere ‘volunteer’ but one of ‘the chosen.’ Of course that only happens if the organization really values you. So if you haven’t been abducted yet, it means . . . well, I think you know what it means.

Tempted to say “exploited,” but “recruited” is correct.