It seems to me that if there is no money designated to pay the employees than of course they will need to be put on leave:

The U.S. Forces Korea (USFK) has sent a letter to the union of its Korean employees stating that it will place them on unpaid leave from mid-April 2019, if the ongoing defense-cost sharing negotiations between Seoul and Washington are not settled by the end of this year.
Korea Times
In the letter to USFK Korean Employees Union President Choe Ung-sik, USFK headquarters’ Chief of Staff Maj. Gen. Michael Minihan said, “Unfortunately, unless the ongoing SMA negotiations can be completed in a timely manner to avoid a lapse in labor funding, we will be required to issue a general furlough notice.”
“Unless a new SMA is agreed to, it will be necessary to implement the furlough effective April 15, 2019,” Minihan said.
This is viewed by some observers as an attempt to gain concessions from Korea as the negotiations over sharing the cost of stationing American troops here are making little headway. They say that the U.S. is “taking Korean workers hostage” to demand a bigger payment from the government.
Time has been running out in the negotiations in relation to the Special Measures Agreement (SMA), a five-year defense contract between Seoul and Washington. It will expire Dec. 31.
The notice may possibly affect as many as 8,700 whose wages are co-paid by both the government and the USFK.
You can read more at the link.









