Interesting, but a couple points:
1) No need to step out of bounds on a change of possession.
2) If you go down 10 you're pretty equally screwed so I don't know if that's really any better than allowing a 1st.
Here would have been my idea: run all the way back and take a safety. You're down 23-20 and now you can try an onside kick from the 20. If you get it, you can tie with a FG or win with a TD! If not, you're in no worse of a position -- Lions would have the ball on the edge of FG range and you still have a chance to beat them if they get stopped on 4th or kick a FG.