Delta 9 ---> Outside Scoring - mediocre(high)
SlipNslide --> Perimeter Defence - respectable(medium)
Delta9 ---> Inside Scoring - strong(low)
SlipNslide --> Inside Defence - strong(medium)
Delta9 ---> Offensive Flow - inept(high)
The ratings say that your team's offense wasn't good enough to beat SlipNslide's defence both inside and outside. So, you missed a lot of shots. That's why his players grabbed so many defensive rebounds.
Your inside defence was also too good for his inside offence to beat. He also missed a lot of shots from the paint. However, his C/PF rebounding skill was better than yours, so that's why he grabbed so many offensive rebounds.
From the outside he was very successfull. So, your Guards didn't have chances to grabb a rebound. The most of the shots he missed was from the inside, so the BigMen rebounding was the reason. The ratings give you the total rebounding performance (both C/PF and the Guards) however, the C/PF spots was the key for this game
Hope you understand me...