As far as I'm concerned every country is a corrupt country- every single one- ours as much or moreso than some. In the big scheme of things is there any real difference in a dictator being corrupt and a bunch of oligarchs being so? Or a bunch of bureaucrats? An elected President? Whatever difference is just a matter of economy of scale. Pay offs are payoffs regardless of who gets what. For the people in the bottom 50% of any given country it only matters if they believe their slice of the pie has gotten too small to eat (therein lies the revolution!).
As far as the Ukraine goes, Zelensky would be an idiot not to talk to China. If he could get the Chinese to put pressure on Russia to end the conflict a lot of Ukrainian lives would be saved. Which, IMO, should be a major, if not the major, consideration for him. Yes, we have sent him a lot of aid, but only what was needed to stop Russia short of conquest, not what is needed to win the war for the Ukraine. And apparantly we have no intention of doing so. That has been his argument all along, and frankly he's right. We arent so much defending the Ukraine as we are bleeding Russia (and the Ukraine concurrently).
Let's not forget that ALL of the Ukraine drama could have been avoided years ago if NATO hadnt dragged its feet on the Ukraine's application for membership. If they admitted Romania and Bulgaria they should have had no issue with the Ukraine. Russia would have never attacked if Ukraine was a NATO member.
Looked at in that overall context, inviting China to invest in rebuilding makes somewhat more sense than it would first appear. And besides, whatever the Chinese build in the Ukraine can't be physically repossessed, assuming the "corrupt" Ukrainians won't be as stupid as the "corrupt" African countries that agreed to Chinese military bases in exchange for economic help.
As far as resliing aid, all I can find legitimately referenced are articles about humanitarian aid being siphoned off and sold on the black market. SAd, but not truly suprising. I did find one reference, since discredited as it was a Kremlin-aligned source, that stated the Ukrainians were selling surplus military equipment to African countries. I doubt seriously there is any state sponsored effort to sell Western military equipment off by the Ukranians as it superior to most Cold War era equipment still in their warehouses- it just wouldn't make sense. Corrupt individuals-maybe. Selling old Cold War surplus does make sense however, as the money could be reinvested in more modern equipment.