Dawn gets a Togekiss only 2 episodes before her Grand Festival. Only 1 of those eps focus on her training it, as the one after is a Ditto filler about some crossdressing female who looks like Flint.
Togekiss is used in the Zoey match and feels out of place as it has no history with Dawn or Zoey.
And now that DP is ending, Togekiss is briefly seen in the Meowth filler and so forth but nothing important. And the rest is Ash's league where it won't be seen.
Togekiss was clearly only given to Dawn for a 6th Pokemon, so why have her release Ambipom when there was no reason to do so?