Thanks to everyone for your help. We have been doing pretty much what you suggest, and Sol is better than he was. It's jist hard for Tom (tha't my husmban's name) because our other basenjis loved him and having Sol lie next to him and be petted would be such a comfort, and this all seems to be taking so long… And because when his brother came over Sol was great with him. It is all part and parcel with the many little frustrations of blindness. Tom can still see some-- it is fuzzy and washed out, but he can even put a leash on Sol, who will even stand still politely for it, but is clearly just politely tolerating, not likeing Tom. And he absolutely won't come to Tom. We will work on the Tossing stuff- it seems the best avenue.
In cool stuff, I am a rock climber, and when I go to a local wood to climb boulders sol like to climb them too- obviously shorter ones, but he really likes it, and runs to them to climb-- I have to discourage him with a firm 'no' when it looks too dangerous. I want to do a little video of him climbing. He jumps on stone walls and walks along next to me too. I use treats to teward him for getting to the top sometimes, but he still climbs after I am out of treats.