Well, not to the US, but the US base in Ramstein, Germany.
Part of the reasoning appears to be that they are asking for the US to supply them with used F-16s in exchange.
"At the same time, Poland requests the United States to provide us with used aircraft with corresponding operational capabilities. Poland is ready to immediately establish the conditions of purchase of the planes," it added.
(F-16s were not explicitly mentioned in that Polish announcement, but they were mentioned by the US sources, in the earlier story you've linked.)
N.B.: the US officials were apparently not expecting this:
Under Secretary of State for Political Affairs Victoria Nuland testified before the Senate Foreign Relations Committee on Tuesday and told lawmakers she hadn't heard about the offer while driving up to Capitol Hill. She added, "I think that actually was a surprise move by the Poles." [...]
Later Tuesday, Pentagon spokesman John Kirby said in an emailed statement that the U.S. is "now in contact with the Polish government following the statement issued today," adding that it's up to that country to get the jets into Ukraine's hands.
"It is simply not clear to us that there is a substantive rationale for it," he said. "We will continue to consult with Poland and our other NATO allies about this issue and the difficult logistical challenges it presents, but we do not believe Poland's proposal is a tenable one."
So, apparently the US was less than thrilled to have the "hot potato" passed on to them like that.
Kirby also said "No decisions have been made" on the Polish request to supply them with F-16s in exchange.
As it later transpired, Germany (Scholz in particular) is definitely opposed to transferring any fighter jets to Ukraine.
Speaking at a press conference in Berlin alongside Canadian Prime Minister Justin Trudeau, Scholz said Germany had already sent defensive weapons and "significant" financial support and humanitarian aid to Ukraine.
"Apart from that, we have to think very carefully about what we are doing, and this certainly does not include fighter jets," the chancellor said.
So, Poland attempting to make the US be the party responsible for the handoff to Ukraine might have been a way to (try to) force Germany to accept the move. It's one thing if Poland does it, and another if the ("big bro") US does it, in terms of how easy it is say you're against it, if you're a NATO country.
Later the Polish PM made some of that angle obvious when he said:
"We did not agree to supply planes by ourselves because it must be the decision of the whole of NATO," Morawiecki said during a press conference on Polish television.