I tend to agree with Old Man in light of the way people conduct themselves within our own Ashkenazic community.
Litvishe/Yeshivisha daven and hear Krias Hatorah (even Parshas Zachor) in Chassidishe Shuls, and Chassidim daven in Litvishe yeshivos, and no one makes an issue about whether you are yoitze or not. In fact, in some shtieblach during the weekdays, you can have one minyan laining with a Galiciana Havora, while a half-hour later, another minyan could have a Litvishe kria. It is all accepted, and no one makes a fuss about it.
The issue on this thread, however, was whether the Roshei Yeshiva in an Ashkenazic yeshiva have overstepped their bounds in not allowing a Sephardi Krias Hatorah. Based upon Rav Moishe’s tshuvos, it appears that they are standing on solid ground, and they do have a right as to how they conduct their tefillos and minhagim in their own yeshiva.