Hi I had very similar prob;em and for the life of me I couldn't get that long r/h side tight, so the cam wheels lined up the crank was out by about a tooth.
Hope this makes sense: I fitted cam belt around tensioner, water pump and around both cam wheels (Locked). I found by sliding on about half the width was workable and with the bottom of the belt pulled like crazy to get the r/hand side tight and on the crank pulley. I set the belt back onto all pulleys and tensioner etc, and it lined up.