I'm dead in the water because the site I need is down

If critical need a backup resource, if possible. If a vendor site hold them to the contracted SLA.

Its randomuser.me

Free API but they should still implement a resilient infrastructure. Or you need a backup resource you can use in disruptive events such as this. When evaluating commercial vendors always check their infrastructure - especially cloud vendors. Also ask for their business continuity and disaster recovery plans. If they have none - keep looking for a vendor.

That sucks. I've never heard of it, what does it do?

I'm thinking of the ripple effect, maybe you were depending on them, but they were depending on left-pad... pay it forward!