Those serial numbers take a bit of work to figure out. Unfortunatly, if it is stolen and recovered by whoever, they probably will not take the time to find/figure out the serial number.

Dodsun has been around since at least the 1970s. They were one of the manufacturers of Swing bikes, an almost fad from the 1970s. More recently, there are Dodsun brand name bicycles. I don't think that you need to worry that the quality is poor, it isn't.