If you filled the hole with cement, then the odor is not coming from there. To find out, open a large plastic garbage bag and place it over the cemented area. Tape the edges of the bag to the ground and wait 24 hours. Open the bag and smell it. If the odor is coming from there, then it was obviously not sealed properly. The best thing to do is dig up the cement and redo it. It is more likely that the odor is coming from some source of condensation in the basement. Water pipes that run inside the wall often develop condensation that can carry odors. Concrete covered with insulation that is not properly sealed is also a common source of basement odors. Insulate water pipes against summer condensation, use vapor barriers on insulated walls, and seal electrical outlets airtight.