When thinking about Zelensky, I thought he's in over his head... but then I remembered the great quote from ... someone: If you're not in over your head, you won't know how tall you are. "In over your head" is an expression used by bullies and fascists to put down those who are struggling against powerful enemies.
It's a T.S. Elliot quote (I cheated w/ Google). Seems like it's true even in the event of failure. Everyone fails, life is mostly a matter of how we choose to react to those failures (so cliché, but unfortunately true). Zelensky has walked a verrrrry fine line, but the exact timing of the whistleblower's complaint finally reaching congress in early September was fortuitous. Zelensky had been effectively strong-armed by Trump, and booked a CNN slot to announce an investigation into the Bidens, but the military aid was released in the interim. It's actually another piece of evidence demonstrating how crucial the aid is considered by Ukraine. I wouldn't consider it a failure by Zelensky. He clearly didn't want to do it, but had no choice.