Well, this part of your argument falls down, because we simply don't know how many ways life could exist.

We really don't know how common life is - whether the Earth is the only living planet ever, or whether it's quite common in the universe.

All the information we have is negative - we see no trace of life anywhere off Earth.

Occkam's Razor would tend to lead us to, "We are alone in the universe." Without any other evidence, this is sadly the way to bet.