Sending a mail with attachment on failed expect - protractor

Question

I am trying to attach a .png file to the mail that will be sent via nodemailer on a expect/spec failure run via Protractor.
Worth mentioning is that I am using protractor-jasmine2-screenshot-reporter for screenshot capture.
What I am doing:
browser.driver.wait(function() {
return helper.checkURLAddress(browser.params.Test.URL.mojOLX); //will return false
}, 2000)
.then(function() {
// success code
},
//failure code goes below
function() {
var htmlFilePath = 'D:/Test/target/screenshots/my-report.html';
var htmlFileContent = String(fs.readFileSync(htmlFilePath));
var screenshotDirectory = "D:/Test/target/screenshots/chrome";
helper.sendHTMLMail(htmlFileContent, helper.getMostRecentFileName(screenshotDirectory));
}
The function for getting the most recent file:
function getMostRecentFileName(dir) {
var files = fs.readdirSync(dir);
return _.max(files, function (f) {
var fullpath = path.join(dir, f);
return fs.statSync(fullpath).ctime;
});
}
And the mailOptions with attachments:
var mailOptions = {
//from, to, subject go here
attachments: {
path: htmlFilePath
}
};
The error I am getting is:
Error: ENOENT: no such file or directory, open 'D:/Test/Screenshotname.png'.
The filepath of the screenshot is actually incorrect and is missing 3 directories in the path to get to the PNG(target, screenshots, chrome).
I pressume that it is due to the directories not created, as mentioned in this thread. But the solution here is to wait for the pdf creation, which is done by the user, which is not the case here.
When exactly is the screenshot saved?
Why does the function not use the file it shows in the error?
EDITED Question:
How to call the sendHTMLMail after the screenshots are created?