I think this has been covered before, but is it इस because it's in the oblique case?
Same question, what's the difference between यह and इस in this sentence?
यह is direct case, इस is oblique case.
I believe they are interchangeable here.
My first answer was marked incorrect when i used them interchangeably
Why does इस take the oblique case but not यह?
इस is the oblique case version of यह. It's like him vs he.