Many years ago I was leading services at a small Steibel, and after Schacharis Amida, sat down to Tachnun, despite some old guy screaming at me to say Kaddish. After services he was so livid at me for having no respect for his revered Rebbe, whose Johrzeit was on that day.
I made it as clear as crystal to him, that my recitation of Tachanun had absolutely nothing to do with disdain for his Rebbe, and that I even recite Tachnun on Adar 7th, even though clearly I respect Moshe Rabbeinu, but quite simply:- Schulchon Orech makes no mention in the list of dates of Tachnun omission, neither of Adar 7th, nor vis a vis private dates, of any Yohrzeit like say for a Beris or Chosson. Despite my response to him, he remained livid at me, but clearly I had nothing to apologize to him about, being that I was conforming to the Shulchon Oruch.
So to answer your question Gubbish, you should absolutely have recited Tachnun today, and you Gefen should absolutely recite Tachnun tomorrow Monday.
When I find myself at some Minjan not reciting Tachnun on a Tachnun day, I recite it quitely as per a Pesak from my Rosh Yeshiva ZTKLLH’H, and if I know ahead that they will be omitting Tachnun when it is supposed to be recited, will already recite Tachnun after silent Amida prior to Chazoras haShatz.