Not sure it'll fail, but I am pretty sure, if the Patriot is sent at all, it will be the PAC-2 missiles with upgrades.
How it performs in an AD role will definitely be interesting.
The US definitely needs a massive air defense upgrade, but that belongs under the US military thread.
Which uses Patriot, but will be replacing it with a local product. Given the age of the Patriot, that's not surprising.
Supposedly, the US built over 1k launchers for Patriot and has 480+ in active service. If the other 500 or so are in some sort of stockpile, that will be quite interesting to watch.