Has anyone been recalled from terminal leave?

Presuming you're talking about final terminal leave off active duty, yes. I was processing out against a mandatory DOPMA date and terminal leave got ate up by me being "essential" to a US Court of Claims Case. I wound up working for the Navy as a GS-12 and had the honor of US Marshals dropping a subpoena on me at Camp Pendleton in front of all the office staff. We all had a laugh as all I needed was TAD. DoJ thought it was funny too, but at the time the case really went forward, they didn't know my status. Just another of many anomalies in my life.

I knew a guy in Germany that was on his first day of Terminal leave, was at the airport boarding the plane when MPs took custody and brought him back to base.

It depends on the reason for the recall. I remember a case where a retired Soldier was recalled to active duty to face court-martial charges.

I had to bring back someone from terminal leave in Korea. They had to flight him back and put him in the whole for leave because he wouldn't come back. It was a mess!

The few times I've seen it was for UCMJ action. SM decides he has his DD 214, time to go tell off that one NCO/Officer they don't like. Next thing you know, terminal leave is gone, the SM is flagged pending UCMJ, and they can't leave the service until it's complete.