You want to be absolutely pedantic about torture "meaning specific things", and where "commonly-accepted definitions" happen, conveniently, to mean what's more convenient to you.

Dictionaries, on the other hand, define torture as "inflicting pain and suffering on".

The UN Conventions on Torture in no way specify that imprisonment, formal or otherwise, is a required component for something to be defined as torture.

So my opinion is that your vision of torture in this instance is far more narrow, because it fits your worldview more.