Do you have any alternatives for someone who doesn’t have access to a grill?

frying pan or oven will give you the char you want .

I live in a climate where grilling outside, while theoretically possible, is not especially comfortable. Dumping rain, wind, snow, no. I have a ridged cast iron grill pan that I use on the stovetop. Being cast iron, it gets wickedly hot, retains the heat well, and leaves those seductive grill marks. If something can be grilled, I've grilled it in it.

P.S. I got mine at TJ Maxx, and I know I didn't pay more than $15 for it. It's still one of my best investments.

In the headnote, the recipe author says both that the star of the recipe is the dressing and you can roast in a 400F oven if you have no grill.
If no oven, try in a cast iron fry pan on stovetop.
The recipe sounds delicious and I've added it to my "to make" list!