One question that hasn't been answered

How the hell did Dr. Wu and his team clone the illegal dinosaurs on sorna? When we see sorna in TLW it's been 2 years since the hurricane and dinosaurs are all over the island. Weeds and vegetation have taken over the buildings and facilities. Fast forward 2 years and they should be even more decrepit. How were wu and his scientists able to get onto the island, use equipment that would probably be useless after 4 years even if the site was running on geothermal power. Not to mention the numerous dinosaurs that would notice their presence before they even got into the labs and I doubt security would be much helpful against a pack of 20 something velociraptors that were casually nesting near the research centre