Kevin Strother, the man that designed the black knight for Oregon Bow Company (the fastest bow of it's time)once designed, and maybe still does,for BowTech. I think Oregon Bow was bought by a company called Horizon Bows, which I think is defunct as well. There is a Horizon Bow company out there now, but I'm not sure it is the same one ,but here is their link:
http://www.horizonbow.com/. I have heard some say that Bowtech is who bought Oregon. Maybe this will give you a starting place, but I doubt any company, that has chaged its name anyhow,has to honor a warranty of another just because they bought it out. Some will do it, such as when Redfield was bought by Blount, but in that case, Blount wanted the Redfield name, and thus honored the old warranties.