someone told you wrong. You might actually get some sexed color pattern since barred is sexlinked in some since. but a white roo to a barred hen is not going to work like the black sex link which is a read roo to a barred hen. Your roos may or may not have the silver gene, but he doesn't have the color needed to off set the silver gene the hen does have. Your pullet would likely not be barred once feathered, the roos definitely would be barred. I doubt they would be identibiable at hatch.