If the funded research is bad -- and it is an area of interest (political, social, industrial, etc) -- then it won't survive for long. So you are correct, if Philip Morris funded bad research relating to the mating habits of fruit flies in a zero gravity environment - it is unlikely to be challenged in a timely manner... but as nobody cares, it doesn't matter.
They should have known it was bullshit (in Frankfurt's technical sense [0]), though.
[0] https://en.wikipedia.org/wiki/On_Bullshit: "As such, bullshit can be neither true nor false; hence, the bullshitter is someone whose principal aim—when uttering or publishing bullshit—is to impress the listener and the reader with words that communicate an impression that something is being or has been done, words that are neither true nor false, and so obscure the facts of the matter being discussed"
tbh, the NFL was smart to lump so much money as a promise to the NIH, pitting all of the institutes against one lab at BU.
I assume concussion research was like this for a long time: they were just trying to find the best way to heal brains after damage, and it was fine to take money from whomever would fund it. Then suddenly there's a question relevant to policy: do football players suffer a lot of permanent brain damage?
In fact it's crazy that such research would be funded by an organization that would be destroyed if the answer turned out a certain way. One should expect no better than with cigarette companies funding lung cancer research.