There is an event that will start to run on the 26th for the Eon Ticket, which will allow you to catch Latias in Omega Ruby and Latios in Alpha Sapphire and they, probably, have the Soul Dew.
The problem is that the original distribution for the Ticket will be only for a few players in a special invitation-only event in the UK (for European games), in a limited distribution in the New York Nintendo World Store (for American games) and as a code in the current Coro Coro magazine in Japan (for Japanese games)
It is also announced that, at least in the USA, it will be obtainable at future Play! Pokémon events.
The good part is that an original owner can share it with other players using StreetPass but that doesn't help you if you don't live nowhere near one of those places and/or you don't meet with an original owner, like players in Australia, South America, Continental Europe and Mainland Asia.
Those people hope that, even if an original owner does not step foward and share the wonder card data at least one of the receptors will do it, so, with a compatible editor, it could be replicated in their games and be given to those players around themselves.