You can still apologise for the situation, almost like giving your condolences. Just acknowledging the other parties hurt by saying sorry shows some solidarity, and can go a long way.
It might also be worth it to view saying sorry more as a proposal rather than a "confession", and then let the receiving party feel if the reception of the apology is warranted. It might help them sort their feelings out and recognise that you're not to actually blame. One has to receive a forgiving, and sometimes there's nothing to forgive, and saying sorry helps with coming to that conclusion.