> Sounds like this is less about whether RoR was the right tool for the job and more that no one other the implementer was familiar with Ruby/Rails (and maybe not even them).

Isn't that already an operational problem? I mean, consider the mental burden alone of being forced to onboard to a completely different and relatively obscure tech stack, including the quirky programming language that serves as it's base, and all just to keep a web service up and running.