What I fear is that he's technically right - because he'll use Hungary's position as an EU member to tear up and otherwise interfere with EU attempts to fund Ukraine (something he's not able to do to the US) and do it well enough that Ukraine's position in it's war of self-defense is seriously compromised.
The other countries can just sign other agreements outside of the EU framework to bypass Hungary. Or maybe they will grow a pair, kick Hungary out of Schengen and make the border crossing painful enough to crash Hungarian exports.
Hmm. Could they legally kick Hungary out of Schengen without its approval?
Agreements outside of the EU framework - now that is indeed a clever workaround. I seem to recall similar maneuvers during the Greek financial crisis when the UK wouldn't agree to things.
Since Hungary is letting russians in unchecked amidst a wave of sabotage and terrorist acts by russian agents, they can use article 29 of Schengen Border Code to suspend them.
That's been dismantled already. He already tried it and failed. EU managed to work something that doesn't need Hungary approval to be done. It was a small step toward confederacy, which is is a nice turn of event if you ask me.