To be honest i dont think you can base the progeny on eating slugs & scraping saw dust into the bedding area, i have seen ferrets do both the things you describe , what limited experience i have with polecats is they behave very diffrently , they skulk, they dont crap in one place & i think most importently they dont smell the same as ferrets , and of course there nocturnal generally
What i will say is if these kits are 75% polecat then as they grow they will no doubt behave differently to a ferret, so homing them is going to be hard , making sure whoever takes them is 100% , they