I just jumped someone yesterday and I did not get a ground either at first, ( I used the strut bolt as marked) I wiggled it around and noticed that the nut did not ground but the bolt did??? Once it was grounded to the bolt, the other car started no problem I guess the nut is not conductive

 

It's all fun. Don't let me ruin the party.

 

I think that is the answer we have been looking for.