As stated above, it's possible. You'd need to carefully compare your reports to confirm that the only differences among the CRA's is the inquiries and you also need to confirm that the scores you're referring to are all the same scoring model. However, as pointed out above, even if report data and model are the same there can still be differences in scoring. 20 points isn't much of a difference. It's about the minimum threshold of what I'd recommend looking at. However, you're better off focusing on report data versus just obsessing over numbers.
