he wanted to go on the roof to help/assist kinemon first off just like luffy did here
kinemon didnt need rescuing here. he learned the scabbards were in danger through black maria's call.
more like he got involved with a plot on black maria
and the people who oda wanted to be on the roof fight got to be there
where yamato told momo they will be the ones to take down kaido.
"That’s why he didn’t go there after learning Kinemon wasn’t there anymore"
didnt go there cause that isnt his fight
isnt sanji's
isnt jinbei's
isnt franky's
and so on