You don't have facts with the money find without knowing exactly how it got there, the same for the placard. you are basing facts on assumptions and speculation. the river flow has nothing to do with the flight path.
These are all critical.
1) The money arrived on Tena Bar somehow. It either arrived via natural method, or, human intervention. There are no other options short of the Holy One getting involved. In order for the money to have arrived via natural method a whole series or remarkable things have to take place. That said, it had to be deposited upstream from Tena Bar. This is impossible if Cooper jumped at 8:12. Unless, the FBI was very off on the jump time, or, the FBI was very off on the jet location. Otherwise, human intervention is the only other choice.
2) The placard arrived after being blown from the jet at 10K feet up. It fell to earth for several minutes in an atmosphere that was flowing briskly to the northeast. We (me, you, the FBI, everyone) are able to reverse engineer this to determine where the jet was when it flew out the back. That is a perfectly legitimate endeavor to ascertain the jet location at that moment in time.
3) The river flow pertains to the money on Tena Bar. So, yes, that is very important.
Let me be clear on this point. Something doesn't add up. There has to be bad data here somewhere. That is also a fact. All of these data points cannot be accurate.
