Hm, no I really meant 'lower bound', as in 'we have seen x events in y days to date, so there can't be fewer than that'. And then you'd have to adjust that as more evidence rolls in.
Not an unreasonable conclusion, but let's say there is a true (hidden/unknowable) rate of deaths X. You'd expect, not knowing the statistical distribution, maybe half the time the measurement (adding deaths from events) it'll be less and half the time it'd be more, just like any other random variable measurement. So it isn't a lower bound, just a fantastic guess that's bound to be pretty close. How close will it be? Well, the sample size is pretty low, so honestly it could be quite wrong. This is what the mega-parent was saying.
edit: you can get a lower bound, from a statistical perspective, the same way, where you go out a couple standard deviations to make up for small sample size, e.g. terrorism is more dangerous than being hit by two meteors at the same time, but if you wanted to make the case terrorism is more dangerous than something strange like water overdose that's probably true but not a lower-bound level statistical certainty.
edit: you can get a lower bound, from a statistical perspective, the same way, where you go out a couple standard deviations to make up for small sample size, e.g. terrorism is more dangerous than being hit by two meteors at the same time, but if you wanted to make the case terrorism is more dangerous than something strange like water overdose that's probably true but not a lower-bound level statistical certainty.