I cant seem to find my original thread, so im reposting it.
Basically, when you go to put jessica in the trunk, make sure you have at least one satchel charge. Throw it onto the trunk, and press whatever button it says to put her into the trunk, but immediately after, detonate the bomb, this must be done in what seems like the same second, or it wont work. after the short cutscene, you will be brought to the mission failed scene, when you get there, exit the mission, and you should be in jessicas car! NOTE: this can not be done on mission replay.
(also for any who say i didnt find this first, i did. just ask J from SRM and he'll tell you i found it first.)