I think Tony's question has been answered. May I add my take:
I am not privy to the minds and motivations of individual members and representatives of the MSM, so we can only guess and speculate why the Harrit e.al. paper has been "ignored" by them.
Surely, the obscurity of the publishing venue along with the fringeness of the claims and the unimpressive c.v. of the authors wrt the specific scientific discipline (which really is "forensics") are all major obstacles to speedy journalistic attention. If any MSM journalists hear about it, it's not from the scientific world, not from leading forensic conferences, not from raging debates among world-class peers, but from fringy internet forums and angry young men shouting slogans on NYC streets.
Next up, the paper is, as most scientific paper, a difficult read for most journalists. In order to tackle it on its own merits, the journalists ought either to be a trained forensic researcher, or consult experts.
If and when either of these is the case, then the third and final reason why the paper doesn't get coverage kicks in - the reason why it SHOULD NOT be presented in any media as a "sensational" forensic find:
The conclusions are wrong! They not only do not follow from the data presented, they are actually contradicted by the data!
As a matter of fact, even Harrit e.al. themselves saw immediately what every forensic expert will see immediately: The chips are paint. They look like paint not just from visual appearance but also in microstructure; and nothing about them say "thermite". There is so precious little overall Al everywhere! There is so much red pigment everywhere, and this red pigment so obviously does not get reduced when the chips are burned (residue is still red). There is such a huge energy release - so much more than what thermite can do, that a few quick numbers will convince everybody who understands reaction enthalpy that almost all, if not fully all, of the measured energy release must come from organic combustion on air.
So Jones found paint. This ain't sensational. It would be a major embarrassment for any quality media outlet that runs the story as if Harrit were right.