If you obtain your own defects report you then have a sound basis to seize the initiative. To retain it, set a proactive agenda including having a plan for how to deal with the defects. The independent experts’ report will tell you what defects there are, the mode of rectification for them and sometimes even provide a rectification scope. If you follow the right steps, you will get ahead of the developer. If you do, then you will be able to sort the defects out when the owners want them sorted out rather than when the developer gets around to them (if ever!).