Here are the previous discussions:
You can’t use ranges to limit because you don’t know what the environmental factors are, but something you can experiment with is detecting cases where the top n-best and the second-closest n-best are close and the overall range is large. i.e. 1-best is -50000 and 2-best is -50500 suggests to me that it’s a close call. But you can’t say “below -50000 is wrong”.