Any tips for adjusting the tenderness of the spaetzle?

Using whole milk, or in your case- 2% milk and heavy cream makes for tender baked goods and noodles. That's because fat coats flour proteins, which affects the formation of gluten chains which give a chew factor. 2% milk contains half the fat of regular whole milk, and adding the extra cream may simply have been just a bit much fat. I know- it's confusing, because it's labeled 2%. You might think that means it contains 2% of the original fat, but that's 2% in relation to the weight of the milk. Whole milk is technically about 3.5 - 4% butterfat. And of course, cream is nothing but pure butterfat. I happen to be in the firm spaetzle camp myself- so I tend to use only water when I make them. However, I have been known to use half water, half milk if I particularly want a softer end product. It also helps if you do beat the batter around a bit, to help develop that gluten. You can also add in more flour if you want a stiffer dough, and of course, a denser and chewier spaetzle noodle. I learned to make them from a very German Oma, who scraped them from a board with a knife. I have a press, so prefer a less stiff dough than she used.

I don't think it's the tinkering with the dairy. This might be a recipe that produces light and fluffy spaetzle that is more tender. There seems to be other recipes that produce a firmer spaetzle.

According to this blog, https://www.daringgourmet.com/homemade-german-spaetzle/, the author mentions beating the spaetzle dough for 15 minutes. I think this helps develop the gluten, for a chewier end product. She also mentions that cooling cooked spaetzle in ice water to firm up the consistency.

Best of luck. Let us know how it turns out.

Original poster here apologizing for the autocorrect from spaetzle to spittle. Yuck! Sorry.