they may be a rumor, or they may be for cell phones only (symbian)
they might have been planned, but never released to public
this is a "Sales rep" site. (promotional). they have pictures of these mystery games. but no downloads.
maybe this is where the rumor started.
the programming company posted images of "work-in-progress" games to promote the dingoo.
if they did exist, they would only be short demos.
even "7 Days salvation" is an unfinished demo.http://a320.bluwiki.com/go/Native_Software
says -- Dream Drift-None Available, and Hell Striker-None Available
notice that the pictures that exist of HS & DD are VERTICAL (like a cell phone),
most dingoo games are HORIZONTAL.