There really isn’t any reason he should be, unless he’s an unannounced presenter or attending as someone’s guest. Dot’s category was presented at the Creative Arts Emmys, and those were awarded last week, so there isn’t even anyone from Glee nominated tonight. I wouldn’t rule it out entirely, though. It’s still a good show.
For those who are asking, his publicist has several other clients. At least one, Sarah Paulson, is nominated for am Emmy this year. Just because she’s in town doesn’t necessarily mean she’s there for Chris, even if she’s hanging out with him (and his cat).