Google-sheets – How to share different tabs in the same Google Sheet with different people/groups

The code below will get all unique names from the sheet names 1 through 14 sheets and perform a summation.

Code

function getTotals() {
  var ss = SpreadsheetApp.getActiveSpreadsheet();
  var uniqueNames = [], allData = [], output = [];

  // itterate through the sheets and retrieve info  
  for(var i=1; i<14; i++) {
    this.sh = ss.getSheetByName(i); 
    this.lRow = this.sh.getMaxRows();
    this.names = this.sh.getDataRange().getValues();
    var a = this.names;

    // gather unique names and data
    for(var j=4, jLen=a.length; j<jLen; j++) {
      if(a[j][1].length > 0) {
        if(uniqueNames.indexOf(a[j][1]) == -1) {
          uniqueNames.push(a[j][1]);
        }          
        allData.push([a[j][1],a[j][2],a[j][3]]);
      }
    }    
  }

  // sort all the data for efficient processing
  var sData = allData.sort(), sNames = uniqueNames.sort();

  // itterate throught the names and perform sum
  for(var l=0, lLen=sNames.length; l<lLen; l++) {
    var sum1=0, sum2=0;
    for(var m=0, mLen=sData.length; m<mLen; m++) {
      if(sNames[l] == sData[m][0]) {
        sum1 += sData[m][1], sum2 += sData[m][2];
      }      
    }
    output.push([sNames[l], sum1, sum2]);
  }
  return output;
}

Remark

Make a copy of the spreadsheet and goto Tools>Script editor

Example

I've created a copy of your file and added the solution to it: Sum Through Sheets

In case it helps anyone else in the future, the solution I've ended up pushing for is creating an Add-On to reference the sheet they wanted hidden. The other workbook / Spreadsheet is:

• set to only "people in the domain with the link can VIEW"
• The tab / sheet is hidden and protected, and
• The document is set to be copy, download, and print protected, just in case someone does find it via spreadsheet key

The add-on itself will be a domain-only add-on, and auto-installed via policy for those who should have access. I believe this should be sufficient protection for what they need.