Is 45,000 years a bit of a stretch for radio carbon dating or not? The half life of C14 is 5730 years, so we are talking only a 231st of the normal amount of C14 to measure.
The theoretical limit used to be 60,000 years (based on the sensitivity of the equipment then available); the practical limit is 50,000, used to be less, and 45,000 is not a bit of a stretch.