They should seal it as a good faith gesture.. re-sealing with the Dicor is not that difficult.
That being said, sealant and/or resealing is defined as a maintenance item, so I wouldn't be surprised if Jayco won't pay for resealing.
I don't understand why a 2016 would require re-sealing so soon. Are the four spots related in any way to the cap work the selling dealer performed?
2016 Jay Flight 38FDDS