Try this. Opt into the beta by right clicking on VRchat in your steam list, properties, then betas. change the dropdown menu to “open beta”. Vrchat should say it has an update available.
Get the update, then when it’s done undo what you did before and opt back OUT of the beta, changing the dropdown menu to “none”. VRchat should say it has an update again. Update, wait for it to finish and try launching the game again.