It wouldn't surprise me if it's Rollercoaster Tycoon 3, at least. It definitely fits the naming convention I'm used to.
If so, yeah—that scratches a kind of itch real nice. I used to be really into RCT3. RCT2 was my introduction to tycoons and sim kinda games when I was in like kindergarten, and it probably played a big part in my video game tastes since. I've shifted over to Parkitect these days: it's got a nice balance between the logistics/business end, building up a theme park, and the detailing. I try to get into Planet Coaster every once in a while, but I end up feeling like it gets tantalizingly close with letting me do stuff I want, but something would somehow feel lacking. Planet Coaster's path building mechanic comes to mind.
Sometimes I'll still boot up RCT3. Its mechanics aren't quite as robust as modern games in the genre, but the rides and attractions set and the aesthetic somehow manages to feel evergreen to me.