Send in the LOCI and then forget about it. Nothing more you can do to improve your chances.
Schools like Columbia use the waitlist only to fill any unmet institutional need. They don’t have an under-enrollment problem.
Therefore, it’s my personal opinion that at such schools the waitlist LOCI doesn’t move the needle in most cases.
So don’t stress too much about the LOCI. Submit it and focus on selecting one of your other schools. If you’re lucky you might get off the waitlist at Columbia, but you should keep expectations very low.
Good luck 