Technically he can’t but right now the Democrats have total control of Congress and the Senate, he could put forth a solution to Congress that would very likely pass.
Everyone is looking for political cover instead of stepping up and proposing a solution. If Biden sent Congress a solution to the strike, the Democrats would go along because it’s Biden’s solution not theirs.
Biden wants no part of forcing a solution, if the strike happens and the economy really stalls, he can blame it all on Congress instead of his lack of leadership.
Then what’s the issue? Read the details of the story. Biden is pressing Congress to simply force the solution that that was already negotiated back in December. Case closed. No need for any more negotiations at all.