Some sentences for reference to clear my misunderstanding regarding would

I think you are right that these are not actually conditionals at all. I think that they are a different kind of construction, expressing that the statement is not known but is a surmise, deduction or suggestion.

"Would have" here is the past of "will have", in the particular meaning of "I guess or surmise or deduce or estimate that".

You can imagine them being shorthand for something like "I don't actually know what happened in Ludhiana when he appeared, but I imagine that there would have been jubilation". In that full sentence, you could say "I imagine that there was jubilation", but if you take out the explicit "I imagine that", then the "was" form becomes a definite assertion, but the "will have" or "would have" form retains its quality of surmise or deduction.

In case 2, this same construction of a surmise is being used for politeness. "When was that, exactly?" would be direct, but "When would that have been, exactly?" is (on the surface) inviting you to surmise when it might have been (though in practice is probably asking you to state precisely and not just guess).