no this tank is fully able, ready, and skipped the cycle. Bac that were on that rock werent dead after you moved wet rock home to use. thats how 90% of aquariums in a huge reef convention are instantly set up so they can sell us 12K$ anemones out of them
your ammonia tester cannot read low level well, your true ammonia would read .00x, something in the thousandths ppm/which is what accurate ammonia tests read across all tanks.
*your tester still has some use. if one of those clowns die, and rots in the rockwork, that api will likely spike back to purple its handy for indicating dynamic change but just not that critical .00x ppm safety zone, they tend to overreport those.
literally only a tester says your tank has a concern, nothing about the actual biology, we can trust the biology over API ammonia any day of the week. the thousands of people who all bought a second round of bottle bac after cycle was complete (or skipped) were felled by the classic inability of api to indicate free ammonia as it exists in a purple coralline reef, in the thousandths ppm.