What I meant by bracketing is just that. Did you calculate exposure, then make a couple exposures opened up a stop or two. I didn't have the luxury of doing that, but when I used to make art photos on E-6 sometimes a shot opened up a stop was worth the effort in my travels.

It was typical for people to make three exposures of things over under and spot on when I worked in labs, I'd see it all the time, thought you might have to, and in this case pushing the film a stop along with the "one over" exposures would have perhaps saved your lunch.