Did I kill my chili's heat by processing the tomatoes and onions together? I made this chili: https://www.youtube.com/watch?v=eQ9eY0_DoEk

I ended up with a chili that, while robust, only gave a mild heat and a heavy tomato/meat flavor, even after excessive salting and peppering. This recipe has two whole jalapeños and half a habanero, so I am not positive this is intended.

There's a few things that could have gone wrong. First, I have never made chili from scratch, so I may have simply under-cooked it. Also, I accidentally added 2 tbsp cornmeal to the spice paste. But, I feel like these are unlikely.

The last difference is what I suspect to be my culprit - I had to blend the tomatoes and onions together in a food processor, due to somebody in the household being a picky eater who can't stand the texture of them. I added it in around the point the tomatoes are added in the recipe, opting to add only the peppers and garlic where the onions would have also been added. 

Did this kill my chili's heat? And, if so, how do I avoid this from happening if I make it again? Or did something else do it? Am I missing something?
So, first, that chili recipe will always be heavily meat-flavored because it has 3lbs of beef in it; at a glance, that recipe is more than half beef by weight.  So if you want a recipe with a subtler meat flavor, that's probably not the right recipe for you.

There are several possible reasons for it being less spicy than you expected, among which are:


the dried anchos and cascabel you used were old and had lost most of their flavor
heat level in fresh peppers can vary a lot; maybe you got ones that were on the less-hot side for their variety
many fresh peppers vaporize a lot of their capsaicin when fried.  So it's possible that adding just the peppers and garlic to the pan could have burned a bunch off; I've had this happen particularly with habaneros


All of that aside, I wouldn't expect that recipe to be super-spicy, more medium-hot.  So maybe you just have a high pepper tolerance.