From my experience in interviewing for pre doc programs, people down weigh your controbution to the paper if youre not the first author and often you have to explicitly make sure to let them know what you did exactly , etc.however I think having a good contribution from your side would eventually lead to you being able to talk more clearly about what you did and show the interviewer that you know stuff. Since you’re in second year, i guess you will be able to work on first author papers which would then strengthen having second or later author papers.