I am aware of only two YouTubers who received them for review, and Adorama may or may not have received any that they might have sold. Pre-orders at B&H and Adorama are not sales, and DJI has already announced that their Mavic 4 Pro warranty is void in the U.S. and the recent Fly update enabling Cloud Waypoint storage is also disabled in the United States. Clearly, since DJI has decided to not sell the Mavic 4 Pro in the United States, they won't be selling or honoring DJI Care Refresh on it either.
So, assuming that two units shipped directly by DJI to two YouTubers for a review were warrantied and able to buy Refresh is premature and unlikely. They were likely received under an NDA, and may also have to be returned to DJI, as DJI may have just paid them for their review, in lieu of giving them the drone.
As previously stated, if DJI wanted to, they could also simply impose a full NFZ over the U.S. for the Mavic 4 Pro. If too many people try and circumvent their U.S. sales prohibition, depending upon DJI's reasons for not wanting to sell in the U.S. (punitive?), DJI may follow through and implement such an NFZ.
Stay tuned.