We're talking about a psychopath here who had (before his capture) and still has every intention of letting the children die.
Obviously would depend upon the exact case (not as if I'm keen to establish a cohort of several such individuals with variable amounts and directions of psychopathy[1]) but for anyone actually so intractible, there's always the chance that they would 'get their rocks off' from failing to provide this information
even under such duress.
Maybe they know they're susceptible to a weak heart or a tendency to aneurisms or some other thing that they are (at this stage)
trying to provoke, with the idea that until their last breath they have exacted their revengism upon the authorities (proxied by the fate of the innocents) by putting upon them the weight of the moral failure to rescue them (not caring themself) and never ever intending to step back from this already rather extreme brink. Perhaps even making it worse, intending to 'break' at perhaps the very last minute by revealing false information to raise then catastrophically dash all hopes.
Who is to say that the victims
are even rescuable. Such a manipulative sociopath could havs set up a scenario where there is guaranteed failure to rescue them. (c.f. the setup of Demolition Man... The villain, it turns out, had already killed the hostages, but in a way that made it look like the Chaotic Lawful hero was branded as their killer - in a rather dark revelation for the rather cartoony 'action plot' that was the general air of the film)
I'm not saying "don't even try", but it seems like all but this one possible method has already been ruled out. In this hypothetical scenario, isn't it now even hypothetically
probable that this means that there
is no winning strategy, for the good-guys? I don't think we'd even get that far (i.e. already promising riches, etc) without a cold decision that there's no point trying to seriously entice the answer from the suspect (though also not stop turning over every warehouse, farmhouse, henhouse, outhouse, in the area and beyond, just in case).
(PS, @Max: I had very much the same idea regarding Osama Bin Laden, post-9/11 (or possibly the as-then-unnamed person that it turned out was OBL, I can't recall how quickly the name officially came out). Despite having no skin in the game (never knew anyone who died on the day, that I knew) I was incensed enough to actually have a means of torture in mind to... I'm not sure what to do. Just a 'death of a thousand cuts'-type thing, except it wasn't with cuts. I think I mellowed a bit on this. These days I think I'd wish to use more of an extreme personal embarassment, if it were in my power to do it. I think possibly there'd be public nudity involved (not mine![2]), but first we'd have to check if that wasn't a secret fetish we should avoid pandering to. Certainly something of a hair-shirt, possibly something of the Henry II (of England) approach, after the Thomas ŕ Beckett incident. ...though it'll never get there, so this is also an extreme hypothetical.)
((Also @Max, though you may feel you're insulated a bit from repercussions, this being far away from (what's left of the still accessible bits of 'Western-biased') Social Media platforms of note. But I'm not sure I'd be even as explicit as you're hedging. Obviously keep in Tarn's good-books, but also don't risk being written down (any more than necessary/unavoidable) in the FSB's own "naughty lists", on the off-chance that traffic-profiling can zero in on you more than you think, ok?))
[1] And get 'an average' between their responses across a range of responses, but risking a corresponding number of groups of victims along the way.
[2] I still have
some respect for the Geneva Convention...