Looking at the pictures of the aftermath, it is not clear to me what went wrong. I would consider the following:
Does the camper have suitable structure to support the jacks? Those skimpy wood screws do not point in that direction. My brackets are attached into solid wood with long, heavy lag bolts.
Were the jacks properly aligned at the start? All 4 need to point straight down with no forward-back or side to side canting.
Was the ground really hard and suitable? Did you use support blocks to distribute the weight for the jacks?
Did you jack up the camper keeping the front higher or at least level with the back and distributing the weight as well as possible on all of the jacks? I recommend using levels, front and back, side to side to help with this.
Did the camper and support start on level ground? It looks like there is considerable slope downward to the right and also downward to the back. That would put a lot of pressure on the right rear jack also make it difficult to maintain a level camper with even weight distribution on the jacks.