Not sure it is possible to ‘freeze frame’ the menu video, but there are some options…
1) make your video freeze frame. In other words, your video will have motion for the 10 seconds, and then the remaining video would be the freeze frame. Of course, you would have to decide how long you want that freeze to be (50 seconds?) before it would loop or play the default chapter.
2) A bit trickier, but just have the motion menu time out to a second menu which looks like the last frame of your video. There would be a little stutter and you would start a new audio track.
Pauley