cynic-al, he wants a race bike and singlespeed will be a hindrance in a race situation. Also open pros aren’t for tubs and tubs really are the way forward for cross racing.
OMITN, vittoria XGs have a similar tread to challenge griffos, dugast typhoons etc so are good in most conditions. Perhaps you could source a pair of michelin green mud tyres to put on a pair of your road wheels for very muddy courses.
Good find on the brakes finbar!