That would only disprove the genetic manipulation part, but not necessarily lab leak. A WIV lab staff can easily contract virus from a bat inside the lab. This essentially what happened in Taiwan, where a lab staff got infected with COVID from a mouse [1]. To disprove lab leak you also have to show either 1. WIV or any other labs in Wuhan didn't have any virus samples that can be an ancestor of SARS-CoV2 2. we can establish a very clear and well understood route how the ancestor of SARS-CoV2 arrived at Wuhan from Yunan province, where the horseshoe bats live, including how it became so good at infecting humans in a very short period of time.
[1] https://fortune.com/2021/12/10/taiwan-investigates-covid-lab...