A work-around without using time-dilation would be to save the velocity as a variable when you pause the game, and then set velocity and gravity to 0. Have the velocity be replaced when you unpause the game, and likewise reapply gravity.
Time dilation sounds like a cool idea, unfortunately I know nothing about it!
edit: It looks like there are two time dilation nodes you can use; one has an input–you might want to try that! If it doesn’t show up, you probably have to disable context sensitive.