Worth noting, though, is that the PRT first needs to know there's something to investigate, to actually go through that modicum of investigative work. And there's also the matter of actually connecting the mysterious new construction to Taylor, which... isn't actually that reasonable, at this point. Realistically, the PRT has a lot more things to pay attention to than Taylor's activities, and that's not even getting to the whole mess of "is this even our jurisdiction?", if the factory is outside the city. While Ziz hasn't destroyed all the orbital infrastructure, it has wrecked a fair amount of it, and there is no guarantee of daily passes at suitable angles by those satellite surveillance systems you mention. How does the PRT actually prove the structure was erected in a single day, if Taylor has fabricated enough (possibly back-dated) electronic records to suggest otherwise?
It's one thing for the PRT to investigate Taylor without the whole thing being hand-waved away, but you seem to be assuming a level of competence, response time and surveillance awareness that the stretched-thin PRT of Brockton Bay doesn't really have. In addition, even if the PRT did somehow have the capabilities to investigate Taylor's activities faster than Taylor's electronic counterintelligence ability can detect it and start covering tracks further, it doesn't make sense for Taylor to immediately be the highest priority target of those capabilities, what with everything the gangs are doing in the city. Quite frankly, it's more likely that Coil will catch on to Taylor's business before the PRT gets the time to do so.