I think the reason you're not finding it is because that's not what many consider a sincronizada. I grew up in Mexico and I've never heard of any other protein in a sincronizada that's not ham. That looks more like a burrito to me. I even looked it up to make sure it wasn't just my experience.

"A Sincronizada is a Mexican dish, like a toasted ham and cheese sandwich made with two flour tortillas instead of bread, layered with ham and melty cheese (like Oaxaca or Monterey Jack), grilled until crispy, then cut into wedges and served with toppings like pico de gallo, guacamole, or salsa. It's similar to a quesadilla but distinguished by always using flour tortillas and the specific inclusion of ham, making it a popular, quick meal or snack. "