Well, there is chance that a part of your brain tries to answer “how much is a stranger’s kid’s life worth?” and returns a number between $50K and $2M. The specific number is censored from the rest of your brain, because thinking of any specific number would make you feel bad.
Thinking about smaller numbers makes you feel “definitely worth it”, to which the PR module of your brain attaches “because human life is sacred”. Thinking about larger numbers makes you feel “nope”, and the PR module searches for a plausible excuse (such as “this is probably a scam”). In both cases, the PR module tries to deny that the actual decision method was comparing two numbers.
However, you are smart enough to realize that all excuses against $2M apply also to $50K. It would be nice if an external authority could tell you what is the correct number, but you are familiar with effective altruism and believe that for $50K you could save more than one life. So you cannot use this specific authority to support your feelings.