This is slightly in error. Jordan "is" Palestine. The original Palestine was divided in two; a sliver which became Israel, and the remainder which was subsequently renamed Jordan.
Jordan is Palestine. Its people are ethnically Palestinian. It is the inheritor of all of what was Palestine, except for those lands awarded to Israel. Any discussions concerning the West Bank concern only Israel and Jordan, and no one else.
There is no chance of an independent West Bank. It will never happen. Its only future is as an integral part of Jordan, or an integral part of Israel. To be allowed to exist as a kind of miniature Afghanistan, a lawless enclave just down the street from Amman and Jerusalem, ruled by killers and mafiosos, is a non-starter. It is madness and leads directly to the monstrocity we see today.
Its future must be determined as part of an agreement between Amman and Israel. If Amman is willing to administer it, then fine. If not, and it seems they are not willing, then Israel must do so. There is no other option. None at all.