I did the calculations myself. Wimbledon website is wrong and live rankings is correct.
If you are interested in details here you go: Going into wimby Serena's points are 8330 and Kerbie's points were 5330. So, Serena had a lead of 3000. As Serena is defending the title, we can remove 2000 from it and so her lead would be 1000. As Kerbie is defending R32 points of 130, Serena's lead will actually be 1130, once we remove last year's Wimbledon points of both players. So, Kerbie has to outperform Serena by at least 1130 points.
If Kerbie wins, she will get 2000 points and if Serena loses in SF, Serena will get 780 points. So, Kerbie would have outperformed by 1220 points which is greater than the 1130 required.
However, Serena is virtually assured to beat Vesnina and if she does that, Serena will retain her #1 ranking even if Kerbie wins the title here. Serena's lead at the end of Wimby in that case will be 430 points.
If Serena wins the title by beating Kerbie in the finals, Serena's lead will be 1830 which will be very safe lead considering Serena is defending just SF points at USO.
If Serena wins the title by beating Venus, Serena's lead over #2 Kerbie will be 2700 points.