Although Elon showed support for Vivek in the Republican primaries, I don’t think they worked well as 1a and 1b because let’s be realistic, Elon had the power at DOGE. I don’t think Vivek plays well as a second in command.
He also had the Ohio governor position he was gearing up for. DOGE isn’t a permanent agency. It will get disbanded next year after they’ve cleaned house in the government agencies. There were clashes on how much time Vivek would devote to DOGE.
Finally, I think Vivek wanted to go about the shut down of these agencies from the legal route. Elon wanted to do it using tech and seeing what was underneath the hood. Vivek stated this as the main difference in their vision for DOGE.