No. No. No.
N.K. demands direct U.S.-N.K only negotiations, without South Korea, because N.K. does not accept the legitimacy of the government of the South Korea. To the N.K. South Korea is just a “puppet”.
It is wrong for the U.S. to have U.S.-N.K direct talks, that exclude South Korea. Do so gives legitimacy to the N.K. claim that the U.S. and U.S. alone can make peace with N.K. It cannot not. Doing so will only endanger South Korea.
If Tillerson is really thinking of doing this, because that’s what the “professionals” at Foggy Bottom want to do, Trump should fire him.
Unfortunately, there is little other option. Unless there is some way to immediately neutralize the 10,000 artillery pieces aimed at Seoul, there is little that can be done to N.K. short of a nuclear strike. What Tillerson has done was basically inevitable (said the same last year, way before Tillerson was in the picture), and I am sure he did not do that with President Trump’s cognizance.