Manchin declines to say 

if he wants Dems to retain

control

“We’re not working for any party. We’re not working for any political idealism,” he said, bemoaning “bickering over political outcomes and who’s going to be in charge..." 

...

...the West Virginia senator fanned out across all five Sunday shows to make the case for his deal. 

That's what this is about for both Manchin and Sinema, attention. They want to be kingmakers. Manchin has his hand on the title and Sinema is having a hissy fit that she doesn't.