The annotated fiora output predicts m/z and int values amended by information on fragment SMILES and adduct.
For the provided example data (compound 'Example_0') it contains a fragment specified as:
81.97246492400001 0.002399961929768324 O=[SH](=O)O//[M]-
The SMILES code indicates a formula of H2SO3, equivalent to a neutral exact mass of 81.97246... However, the adduct is specified as [M]- indicating an electron gain. Hence, I would have expected to find m/z 81.97301... in the output.
Bests, Jan