The Daily Herald is the 3rd largest newspaper in Illinois after the Tribune and Sun. It has more of a presence in the suburbs than the city, but it’s a reputable source.
The shirt brand is Ripple Junction, there are a couple eBay listings for the same shirt and the tag has a 2021 Columbia Pictures trademark on it. Could be donated but it’s relatively new.
This is a man who planned a first degree murder, not a heat of the moment/defense killing. He wanted to kill someone and found an “acceptable” target to do so and people are applauding him? Normal people don’t set up an undercover operation to murder someone.