Sorting or ordering by specific values

This query seems like it should work, but returns "-1" for the first position of the sort on all results:

"sort": [
  -1,
  9678,
  8
]

the query (skuid_text is indexed as a 'keyword' type, and I have verified that the result set includes the SKUs specified in sortOrder):

{
  "size" : "50",
	"_source": ["skuid", "name", "sort_priority","sales"],
  "sort" : [
		{
		  "_script": {
		  	"type": "number",
			"script": {
				"inline" : "params.sortOrder.indexOf(doc['skuid_text'].value)",
				"params": {
				  "sortOrder": [
					"CELCO2017L",
					"CELCO2017G",
					"S21024",
					"WED419",
					"WED420",
					"SOLS2622",
					"FDOR2124",
					"FDOR2125",
					"S21023",
					"CELCO2005L",
					"CELCO2005G",
					"S21022",
					"10171",
					"10172",
					"FDO4124P",
					"WED35",
					"WED37",
					"S2917",
					"CELCO2003L",
					"CELCO2003G",
					"S2769",
					"S2932",
					"S2936",
					"FADRQKE1006W",
					"WED306",
					"WED307",
					"CLAD30DE",
					"CELCO2004L",
					"CELCO2004G",
					"SOLS2466"
				  ]
				}			
			},
			"order": "asc"
		  }
		},
		{ "sort_priority" : {"order" : "asc"}},
		{ "sales" : "desc" }
  ],
	"query" :{
		"bool" : {
			"must" : [
				{
					"term" : {
						"category_codes" : "IRJB"
					}
				}
			]
		}
	},
   "aggs" : {
      "size_apparel" : {
         "terms" : {
            "field" : "size_apparel"
         }
      },
      "color" : {
         "terms" : {
            "field" : "color"
         }
      },
      "price" : {
         "range" : {
            "ranges" : [
               {
                  "to" : 20
               },
               {
                  "from" : 20,
                  "to" : 50
               },
               {
                  "to" : 100,
                  "from" : 50
               },
               {
                  "from" : 100,
                  "to" : 200
               },
               {
                  "from" : 200
               }
            ],
            "field" : "price"
         }
      },
      "category" : {
         "terms" : {
            "field" : "category"
         }
      },
      "birthstone" : {
         "terms" : {
            "field" : "birthstone"
         }
      },
      "size_jewelry" : {
         "terms" : {
            "field" : "size_jewelry"
         }
      },
      "recipient" : {
         "terms" : {
            "field" : "recipient"
         }
      },
      "occasion" : {
         "terms" : {
            "field" : "occasion"
         }
      }
   }
}

I have tried both doc['skuid_text'].value and doc['skuid_text']