If it was me in their place, I’d try giving up as little as possible then seek some sort of binding defense agreement, whether NATO or something else. And if necessary do it in secrecy so Russia doesn’t hear about it until the agreement is fully in force.
Honestly I just think the US is simply not reliable, and with Ukraine seemingly relying heavily on the US, they need to be looking for the quickest exit strategy they can come up with at a moment of strength.
Hopefully, if Republicans prevent continued US support, other countries will still provide enough…I just fear it may not be, and that seems like a worse outcome for Ukraine’s people.