This question: http://superuser.com/questions/596703/transfer-amazon-s3-data-to-mysql-database, was closed as Not Constructive. Before it was closed, I thought it might've made a good fit for dba.stackexchange.com, so I asked in The Heap and a moderator confirmed. I flagged the question for migration (I think I might have hit mod attention?), which was declined:

Asked in The Heap if they wanted this question. Mod said yes. Would probably do better there. – May 17 at 14:42 declined - flags should only be used to make moderators aware of content that requires their intervention

How could I have gone about getting a question like this migrated?

I realize odds are that if a question is not constructive on one site, it's probably not on another, but this isn't strictly true. Aside from Programmers being the obvious exception, there are questions that are on topic for Server Fault and not constructive, but work for Sec.SE. How does SSL work? for example. And while it might not be the best practice, smaller SE sites tend to be a little less aggressive about Not Constructive than SU, SF, SO.