you have to put center in at display name like here
“DisplayName”:“Map”,
“Category”:“ARK Server Settings”,
“Description”:“Sets the map for the server. If Custom is selected, Custom Map Name must also be set”,
“Keywords”:“map”,
“FieldName”:“Map”,
“InputType”:“enum”,
“ParamFieldName”:“Map”,
“DefaultValue”:“TheIsland_WP”,
“EnumValues”:{
“TheIsland_WP”:“The Island (default)”,
“ScorchedEarth_WP”:“Scorched Earth”,
“TheCenter_WP”:“TheCenter”,
“{{CustomMap}}”:“–Custom–”
update your instance and now you can choose the center map and it works for all future maps