not much is known about mr ketchum at all most info is just rumors but many may make sence for example remember the episode were ash awakens spiritomb how much does the legendary trainer who beat spiritomb look like ash?
also one of the anime designers said ash's dad is on a very important journey of his own but how important could it be? personly the one thing ive really wanted is an episode whith ash's dad in it
and finally if you notice that all player characters dads are gone could this be a link could the fathers be working together?