The campaign story dialogue wasn't at DMM launch. Neither was Lavender's story during the first time around.

As for the topic at hand, I won't pretend to be a flower expert (nor do I have the interest in looking further into it), so the inaccuracies of the names don't bother me much. I do admit a lot of them can be weird though, and I myself just default to the Japanese name if it suits me (e.g. Asagao instead of Ipomoea).

As I recall, there were enough complaints to Nutaku staff that they mentioned they'd give later names more scrutiny, but don't quote me on that. Feel free to keep pressuring them if you feel like it.