If your friend didn't break any rules, then you both have nothing to worry about. Jagex will review the report and action it if necessary, or discard it if no offences were made. False/accidental reporting happens more than you think.
It is worth noting that they might action you for persistent false reports, most notably if it's done maliciously. I don't mean to say that to worry you further, but it's still worth having some caution going forward.
24-May-2020 16:54:04