I just started saying Kaddish for the first time. After listening to it for years I didn’t know I was going to trip and stumble over so many words, and stammer with the words that I didn’t trip and stumble over. It’s a tense experience. But I struggle through it, anyway, some days better than others.
If my Kaddish recitation is straggling behind, it’s up to those who will care to hear and respond or not to say their responses. I did the same for others when there would be two or three differently-paced Kaddishes being said. Either someone will respond or they won’t, but that’s on them, not me. It’s hard enough for me, bearing the brunt of a major loss and then struggling to say a common prayer out loud, mumbling and mispronouncing and correcting my words.
As for kavanah and knowing what I’m saying, that’s what the rest of the day is for, to study the words that we daven so that we can say those words in their original language that those prayers were written in.
I disagree with finding a different minyan. If you have a minyan, stay with it, that is your place. “Some cars run more smoothly than others, but they are all cars.”
Better to feel awkward in this world, that it be a kaporah, than have something meted out in the next.