Great idea about checking Universal's YouTube page! I just checked it and they just put up two new trailers for a Barbie movie and a Thomas and Friends movie. So chances are if the Curious George DVD included any trailers, it would have included those and not Journey of the Heart's.
Both of those movies will come out on September 8, so maybe we'll get a trailer for Journey of the Heart then. After all, by that time, we'd be getting close to the usual early December time LBT sequels that are released.