VAERS has always been claimed to vastly understate the extent of injury, disease and death from vaccines. The authors have create a rigorous methodology and use it to predict actual adverse events.
Are the 100 percent right? No. However, anyone who wants to contest these numbers should be as least as rigorous as these highly credentialed authors.
I read in a few places that there was a change to the reporting of a death if was before “X” number of days after a jab? Something about each jab wasn’t fully effective until a certain number of days for it took place, so it wasn’t being considered as a possible cause of any reaction.
Who knows as I believe the entire dataset is in error based on more of an emphasis on sustaining a narrative.