Hi,
I look at your post and catch myself thinking "this is a pretty lucky guy"
.
You live in the city where probably the best ADR doctor works, you only have (I hope) one level, no nerve pinching, no leg pain, lost a lot of weight which is good for your spine, and you do not have to pay the significant amounts of money people from other countries have to in order to get fixed.
I am very surprised you have not seen or heard of Clavel yet. If you indeed have one l5s1 level and otherwise very healthy, he can fix you in a heartbeat; fusion or ADR and you are good to go