I've never seen an underground loco with double-flanged wheels, but I know for sure that those BEV locos will stand a fair amount of fluctuation in the gauge ( the track panels used on tunnel jobs aren't always in the best of order )
a few steam locos used in the NW US and NZ logging operations, usually geared locos of the Shay type, ran on double-flanged wheels - some of the more remote locations used timber rails. Of course there were no points involved
''the stopes soared beyond the range of our caplamps' - David Bick...... How times change .... oh, I don't know, I've still got a lamp like that.