I have never played on a C8B table. Ever.
I have played on an American table, a snooker table and an E8B table. All three are cut differently. If you were to play any game at all, any game, on all three tables - they would be different.
Balls, cut, cues, cloth - all completely different.
So I cannot agree with the point that E8B and C8B are similar and I also contest that winning two major titles in the those two different disciplines with a matter of weeks of each other is some achievement.
To argue otherwise is troll posting frankly.
But the general rules and goals are practically the same.
Tougher equipment doesn't make the game different.
This doesn't mean a player who excels in one variation would excel in another. It simply means that winning titles in variations of one game does NOT make you a champion in multiple disciplines.