Here is one way to use that function to check to see if any file in a given directory is locked.
aFolder = "\\someDirectory\someSubdirectory";
filesInFolder = dir(aFolder);
fileNames = string({filesInFolder(3:end).name})'; % the first two items are not actual file names
numFiles = numel(fileNames);
fileLocked = false(1,numFiles);
for i=1:numFiles
thisfileName = fullfile(aFolder,fileNames(i));
fileLocked(i) = mlreportgen.utils.isFileLocked(thisfileName);
end
if any(fileLocked)
disp("A file is locked")
lockedFiles = fileNames(fileLocked)
else
disp("No files are locked. All is well!")
end