Iranian government does engage in propaganda and deception as well especially for domestic audiences. I suppose if we can get names of these rescued pilots that I trust the US. If the US hides the names there is a chance then that they're lying and the dead will 'die' in a training accident later this month.

Anything short of Iran saying that they have captured them or that their people lynched them is likely just mincing words for propaganda purposes on Iran's part. US would lie about condition of the crew or about no casualties in rescuing or things like that but not likely about whether they actually rescued them or not. At least not for long. They could maybe bullshit it and justify lying to try and convince Iran to call off searching for them for a short while but it'll leak out within a week if that's not the case and they haven't actually rescued them by that time I think.

Frankly the whole being coy "US is lying" but not saying how says it all to me. If they know a definite lie then say what it is. It's so vague as to be useless except for propaganda purposes and encouraging positive thinking about what happened.