As you can see with Manchin, you cannot in fact bribe your way to success in congress. Greased palms only matter to tip the balance of a narrow opinion, any sort of hard opposition will not be affected. Trump doesn't need a majority to scupper any sort of plans that he dislikes, he just needs enough to prevent a majority of voting -for- something.
Addendum: I actually want to rip into this more since it kinda annoys me.
1: This would require McConnell to directly move against a sitting president. Great way to just -burn- any political capital he has.
2: This would require McConnell to suddenly forget how congress works.
3: This would require Trump to do nothing against it at all.
4: it would require McConnell to, somehow as an individual not in the executive branch, have the money and capital to even attempt the bribe.
And I could keep going. In no way does this post begin to make sense as a possibility.