... I have to get another surgery.
The bone scan indicated there was some bloodflow across the gap, but x-rays showed that what is happening is my body is filling in the gap with cells to produce cartilage... to create a false joint instead of bone. Since there is a spot that has correctly fused together, he doesn't want to split the bone completely apart and start over, but what the remedy is will be determined once he actually opens up my foot again. The best option if everything looks good is to clear the wrong stuff out then use a circlage (a wire wrapped around the bone). The worst option, if the bone is too porous, is a plate with a lag bolt (yay, more metal) and the third option between the two extremes is a plate with a circlage holding it in place. In any case, the existing screw will be removed, expected heal time is 8-14 weeks, and I'll be stuck on the couch again for at least part of that. On the bright side, I have all the mobility equipment already so there's no wait time to get them.
Meanwhile, a few days after the surgery, I'll be having guests visiting, which on one side is a bummer, on the other a blessing... Wolf can keep me pinned down so I don't get up before I really should. :)