This happened to my elderly mother. They claimed my nephew (13 at the time) was in a Spanish prison. My poor mother was really distraught. She gave them my brother’s phone number. They actually called my brother. Same scenario as you experienced...call from Montreal etc. We were also quite shocked by the level of information they had.
Similar thing happened to my mother. The weird thing is, her grandson (my nephew) was actually living in Spain at the time, so she got completely freaked out. Fortunately she kept her wits about her and realized it was a scam, but it shook her up badly.
I could happily shoot people who run these kinds of things.