As your question is specifically about IB, it really belongs on the IB forum.

But anyway, both BA and IB have robotics that search for duplicate bookings. Whether they find yours really depends how much information is within them, e.g. it’s plausible for two passengers to have the same name, but if they share a FFP number it’s likely to be identified. Only you (and the airlines) will therefore know the full answer to your question.