What's strange about the Cornell website is that not only do they list him as a senior, but they give his record for 2008-9, 2009-10, 2010-11 and of course there's this year. The Ivy League doesn't allow RS years, so he couldn't have wrestled for Cornell as a RS 2008-9. At least that's how I understand it.
But, if Bosak said on ESPN that he's a junior--well. . . he ought to know!