Thanks for sending the project. I only managed to get the top couple rows to disappear, I never saw all the keys go away like in your screenshots. I believe we've fixed the problem in 3.5.21, available in a few minutes.
BTW, in 3.5 runtimes, you no longer need to key everything on frame 0. We'll be adding something to the dopesheet which can remove extraneous keys for you.
