“Both contacted me to say Thank You”
That is your hakaras hatov! why do you expect anything else? You are a professional, not a friend.
“I politely emailed both Chassan and Kallah and mentioned that in all my years of making Shidduchim I have never missed an engagement or a wedding where I was the Shadchan”
Sounds like you care more about yourself than their simcha. If you truly cared about their simcha you would let them do what they want during this special time and not make them feel awkward.