[Lucky]

This is common with cross-drilled rotors on all cars that are tracked. The prevailing wisdom (and one I trust) is it is a non-issue until you have a "significant" crack that connects one hole to another.

The rotor in your picture has insignificant surface cracking and nothing connecting the cross-drilled holes to each other. It isn't a concern at this point in the rotor's service life.

On a car I tracked often, I would not use cross-drilled rotors. Gas-slotted rotors perform just as well with less risk of failure due to cracking. That's what I used for many years on my 911 track car.