As I see matters you are conflating two separate issues.
Firstly a running or moving average filter will take several samples either before, after or on either side of the current data sample and the function you are using above cannot do that.
Try first using excel or Tableau Public
Secondly, then you wish to additionally also average several running or moving average columns which will not work if the first step is not correct.
APPSHEET can’t give anyone anything unless they program and use APSHEET correctly, the old “junk in junk out” adage.
I think you need to apply your mind a little to this one.