Well, since I've got about several books on the historical development and usage of the various types of biblical hermeneutics that have been applied by various major biblical interpreters through the centuries, as well as about a dozen or two books on the various types of biblical hermeneutics practiced today, along with the more expansive philosophical levels of hermeneutics, and so on and so forth, I'm going to say that your assertion that "only one can be right" is almost a kind of Converse Fallacy of Accident, I think. I say this because simply saying that you've talked to two experts doesn't really mean that you've done enough to understand just how different the interpretations are between these two "experts" you've spoken to, or as to how similar they might be in some respects.
In fact, it seems to be that hermeneutics in and of itself does not involve so much as a 'perfectly correct way to interpret,' since from a human viewpoint, which is always limited to some extent, can't be perfectly informed in all things so as to make a consistently perfect interpretation. Rather, the best we can do is each each individually give the act of interpretation our best shot and to continue to do so in increasing measures as we work through the Hermeneutical Circle. To some extent, our interpretations can all be at least somewhat imperfect and/or incorrect and in need of more information; we can all be on a continuum where we are each wrong in some way and right in some way. The interesting thing for me in this is that this expectation is what also seems to accord with my understanding of Biblical Epistemology.
So, we each can be at least a little right when reading some portions of the Bible, and we can each, I'm sure, be wrong and in need of further learning. This becomes especially evident as one becomes familiar with not only the comparative approaches, but the ways in which any interpreter, whether they be professional or otherwise, compares with another interpreter who may even be (supposedly) working from within the same approach. All we can really do, I think, is try to account for the actual interpretive methods any interpreter claims to us to have made AND the extent to which that same interpreter works by way of inter-disciplinary measures and brings in more data, more information from outside the Bible so as to better understand, hopefully, the meaning and structures by which the biblical messages are being conveyed.