In general (although there are always exceptions) it is the doe that digs the big tunnels, doing all the hard work with the soil excavating.
Bucks tend to just scrape a bunny sized small dig on the surface, then roll in it to scent it 'this is mine'.
They then lay in it and watch the does working hard.
Fellas huh!
Now watch, as half a dozen bunny owners say it is their buck that has tunnelled from their garden to next door just to prove me wrong!
I must admit I caught my male nethie about 8" down a rabbit hole today, which must be spring fever, cos he doesn't usually bother digging!