That's not exactly proof though, there are plenty of counterexamples where a distribution should theoretically be compatible but is not:
- D/P could not receive the Member Card or Oak's Letter from Wi-Fi where Platinum could.
- Various event distributions to B/W could only be received by one or the other, not both.
- In the US, Custap Berry Regigigas could not be received by early release copies of Platinum, only D/P (the event ended March 21 and Platinum was released March 22, but some copies of Platinum were out by March 21 while the event was still ongoing). This might be the closest match to the Emerald AuroraTicket instance.
This proves that Nintendo is able to restrict distributions to particular games even if other games are out and they would theoretically be compatible.
I'm very concerned about this because it causes a bunch of legality issues even on this site, for example, flawless Deoxys RNG'd from Emerald with Gen III only moves becomes illegal, just as non-Japanese Shiny Mew are illegal.
Writing a haiku
With seventeen syllables
Is really diffi--