A way for the host to Forch Jump and Force Mount has been found, use the video below, created by evilKIMARU, for reference...
Non Host
Newer Methods Video by xPandDxProductionsx
1) Go to a object you can jump over.
2) Hold foward and quickly press Down+A.
3) If you hover/levitate over your object hold foward.
4) If you see your guy jump in mid air mount to the object you jumped over, if you jump to another object you will not Force Mount, but instead Force Jump.
Force Jump/Mount Tutorial(Easy, but you need host)
1) Kill another person. (The person must be either killed by a headshot or downed and shot)
2) Have the host move the body in front of a ledge that you want to jump off of. (If your not the host then you will see a fake body)
3) Once the body is in place then push "A" twice to jump off the ledge and you should eventually roll off and float in the air. (The body has to disappear on your screen)
4) You should be mounted elevated on an object across the room.
Alternate Method (Host isn't required, but its hard)
1) Face the opposite direction of a ledge while holding a pistol
2) Push "B" and on your second swing of your pistol you must push backwards and "A."