This video has been posted to reddit as being another MyCoin.hk convention:
https://www.youtube.com/watch?v=SGT3QL5VWPk

It says "MyBitCoin" in the opening shots and many places, but on T-Shirts (mostly in the second half) it says "MyCoin" only.  

There are a lot more than 30 (or 43) people there.  One of the overhead shots shows some large amounts, over 300 M (HKD, USD, CNY, or what?)

If it is MyCoin.hk, there may be a lot more than 43 victims.

If it is not MyCoin.hk, what venture is that?  The overhead texts are in Chinese...