I read, use, and study first-hand accounts quite often and use them liberally in my research.
If it comes between a choice of what you say and what Col Elting writes, then you come in a very distant second.
And there is no need to swear. That just clearly demonstrates that you cannot take criticism of Macdonald who was not the most honest of memoir writers and who was not in the top tier of French generals either. It also demonstrates that you have chosen a path that is unsavory when you begin to lose an argument.
And, yes, I've read parts of Macdonald when necessary, but have found him to be unreliable as in the quotation from Col Elting provided to you.
In short, Macdonald is not a reliable witness when it comes to his own actions, real or imagined. For example, Macdonald claimed to be Eugene's military mentor in Italy in 1809 and he was no such thing. He was a subordinate commander to Eugene, the army commander.