Temari needs to bite her finger, wipe blood across her fan then swing the fan while Sakura only needs to bite her thumb and press down against the floor.
Then Sakura will be raised high up into the air above Temari and Kamatari so once Kamatari is summoned it needs to be pushed upward unless Temari doesnt know she cant hurt the slug then she just attacks the slug to no avail.
Or not even that Katsuyu can be summoned in front of Sakura if needed so Sakura can stay behind the giant slug who can take the full force of the fuuton.
And Katsuyu can split just as quickly as Kiri Kiri Mae destroys a forest. They both happen in seconds.
In that case, Sakura summons Katsuyu beforehand but then what? Is Sakura summoning in front of herself or below herself? Temari manipulates the wind that carries Kamatari in different directions so Katsuyu is bypassed and attacks Sakura head on.
Yeah Katsuyu can split in the same amount of time as a thousand trees are cut but in the amount of time it takes to cut Sakura apart, Katsuyu won't be able to do much.
I do believe Sakura takes this because both Sakura and Temari's attacks cause dust and debris to blind each other. Unlike Temari, Sakura doesn't have to see her opponent to hurt them and to stay safe from Sakura's shockwaves, Temari will have to float on her fan in midair, allowing Sakura to go on the offensive, summon Katsuyu or whatever. Meanwhile Temari is left dangling.