with a vit rank of 19343 will I get cse in vit chennai(category 1)
No chance not at all. Sorry to dis hearten you but that's the reality.There is a cut throat Competition for CSE in VIT especially for Vellore campus but for the sake of category 1 students from rank 4500-7500 tends to choose Chennai campus instead of Vellore in category 2.
So, either it would be 2nd or even 3rd who knows as VIT never discloses any official figure. It is from my personal experience only.
All the best!!