Google-apps-script – Google Scripts DriveApp searchFiles does not work on a specific folder

I am trying to search through some files stored in a specific folder on Google Drive using Google Scripts. This is for creating a "Deployment Folder" for my school for the upcoming academic session.

Code below:

function start() {
    SearchFiles("TextToSearchFor");
}

function SearchFiles(query) {

  //put the source content folder ID and destination Drive folder ID here
  srcContentFolderID="srcID";

  try{  
    var files = DriveApp.getFolderById(srcContentFolderID).searchFiles('(title contains "' + query + '")');
    while (files.hasNext()) {
      var file = files.next();
      var fileName = file.getName();
      var parents = file.getParents();
      while (parents.hasNext()) {
        var parent = parents.next();
        if(parent.getId() == srcContentFolderID){
          //found the correct source of the file. Log it.
          Logger.log("Parent name: " + parent.getName() + " File name:" + fileName);
        }
        else
          Logger.log("NOT FOUND: " + parent.getName() + " File name:" + fileName);
      }
    }
  } catch(e){
    Logger.log("ERROR: "+e.Message);
  }

I am using Apps Script runtime powered by Chrome V8.

I have the following question:

DriveApp.getFolderById(srcContentFolderID).searchFiles('(title contains "' + query + '")') doesn't work. I get the following exception:

Exception: Invalid argument: q at SearchFiles at Array.forEach GS_INTERNAL_top_function_call.gs

Only searching using DriveApp.searchFiles('(title contains "' + query + '")') does work, but it gives a lot of results.
I am trying to do this for hundreds of files, so I risk timing out if I have to sift through multiple search results for every query.

I have looked through StackExchange for quite some time to figure out why an exception is generated, to no avail. Appreciate any help on this!

Note: I have seen the following links:

https://stackoverflow.com/questions/35661979/searching-for-file-by-name-within-a-folder-in-google-drive-using-google-scripts

https://stackoverflow.com/questions/52100052/folder-searchfiles-method-raises-invalid-argument-q-error/52100980

https://developers.google.com/drive/api/v2/ref-search-terms

https://stackoverflow.com/questions/56596130/google-app-script-driveapp-getparents-not-working-as-expected