By Zach Koons Seattle’s worst fears about its starting running back were confirmed Monday. The Seahawks‘ worst fears about the injury to Rashaad Penny were confirmed on Monday when coach Pete Carroll revealed that the running back will miss the rest of the season with a broken fibula. Carroll said on Seattle Sports 710AM Monday that Penny will need to undergo surgery to repair severe damage to to his left leg, forcing him to miss the remainder of the 2022 campaign. The 26-year-old also suffered an injury to his tibia, per the Seahawks coach. The diagnosis confirms what Carroll feared after Sea…