Edit: Oh, you said Matamoros, which is in Mexico and presumably out of the FAA's jurisdiction. Everyday Astronaut seems to think Matamoros is one of the more dangerous parts of Mexico[1] but I'm not one to talk anyone out of adventure travel. Just be wise to what you're getting yourself into.[2]
[1] https://everydayastronaut.com/how-to-visit-starbase [2] https://www.reuters.com/world/us/mexican-cartel-says-sorry-a...
https://twitter.com/VisitBocaChica/status/164693832218955776...
Also the launch should pivot & head out more your-a-way too, which could be cool.
The green areas are the closest you can get by boat. Which is basically just as close as viewing from South Padre Island. You might have a slightly less obstructed or crowded view from a boat versus parking and standing with everyone else on South Padre.
I'm not saying it's a good idea, but, i think if you're sufficiently motivated you can still go inside the exclusion zone.
The Texas side of the border is way safer than Matamoros.
The booster, however, will do a mock landing over the water a ways out from the launch facilities (40 miles I think it was).