Is Asymmetry a novel?

As foretold by various reviewers, the 2nd half/section of Lisa Halliday's debut novel, Asymmetry, embarks on a completely new narrative that, through about 50 pp. or so, bears absolutely no relationship to the first section of the novel (a thinly disguised account of the LH's friendship and relationship with Philip Roth, which, let's face it, is why this novel has gotten so much early attention and which is also why I'm reading it). The second section tells of a Syria-born American citizen stopped by passport control in, I think, Heathrow, as he's on his way to Syria to visit his older brother whom he has not seen in several years. LH does a nice, brisk job recounting the traveler's family background (he is much more "assimilated" than his older brother, who has built his life in Syria/Kurdistan) and the frustrations he's experiencing while being held up at the airport; his itinerary and his "purpose of visit" raise a # of obvious red flags, which he seems not to have properly anticipated - not clear why he wouldn't as he's intelligent and mature. In any event, part 2 of this "novel" seems so far to be a good narrative - though not unlike a # of other novels and stories on the theme of immigration and assimilation (Hamid, Yiyun Li, Ngueyn, to name 3 that come quickly to mind) - but still a good and forever timely topic. I'm taking it on faith that something will tied these two sections together, in particular because the "Roth" section ends abruptly. Are they meant in some way to be narrative opposites (hence the title)? Or is one of them meant to be a mss by the Roth character? I really have no idea at this point, and have to wonder whether these are really two relatively long stories bound together in one book that has been anointed as a novel. (A glance ahdead reveals that here is a short 3rd section that revives the "Roth" character, so that may have something to do with the overall design.)