You write this week “In addition, if you state that you didn’t participate because you were indisposed you are not telling the truth, since you would not have attended in any case. This is derived from a Gemara (Yevamos 65B) that says there is a mitzvo to distort the truth in order to promote peace”.
Why is the question in hand not a case of promoting peace?
Occasionally it might be but generally all you’re trying to do is give the false impression that you are a good friend when really you aren’t . That isn’t called darkei shalom as we see in the Gemara of the barrels. Darkei shalom is to prevent a fight like by Shmuel
All the best