How to find window associated with CFileDialog Open File from AfxGetMainWindow() in MFC Application

Hello everyone,

I am trying to close an MFC application from code. I have added code to save any open documents before the close function is called. I would like to close all open dialog boxes from the application before the main frame exits by sending a close message as shown below:

AfxGetMainWnd()->SendMessage(WM_CLOSE);
PostQuitMessage(0);

I am able to successfully capture dialog box instances within the application (derived from CDialog) and send an IDCancel to their dialog boxes to close them. However, I am encountering issues with capturing the dialog window for any CFileDialog window (either Open File or Save As). I'm only interested in modal dialogs and below is the code I use to capture the window instances corresponding to open dialogs.

vector<CWnd*> GetAllActiveModalDialogWindow(const CWnd* pWnd)
	{
		vector<CWnd*> allDialogWindows;
		CWnd* pChildWnd = pWnd ? pWnd->GetNextWindow(GW_HWNDPREV) : NULL;
		while (pChildWnd)
		{
			if (pWnd == pChildWnd->GetTopLevelParent() &&
				(pChildWnd->IsKindOf(RUNTIME_CLASS(CDialog))|| pChildWnd->IsKindOf(RUNTIME_CLASS(CFileDialog)) ||
					pChildWnd->IsKindOf(RUNTIME_CLASS(CPropertySheet))))
			{
				allDialogWindows.push_back(pChildWnd);
			}

			pChildWnd = pChildWnd->GetNextWindow(GW_HWNDPREV);
			
		}
		return allDialogWindows;
	}

The above only seems to return windows that correspond to dialogs part of my application and none of CFileDialog. Upon using Spy++, I notice that the classname for any dialog (incl. for File Open) is "#32770".
I tried the below code to try and capture all dialogs but once again I only seem to be returned dialogs from my application.

vector<CWnd*> GetAllActiveModalDialogWindow(const CWnd* pWnd)
	{
		vector<CWnd*> allDialogWindows;
		TCHAR szClassName[MAX_PATH];
		CWnd* pWndChild = pWnd->GetWindow(GW_CHILD);
		while (pWndChild)
		{
			::GetClassName(pWndChild->GetSafeHwnd(), szClassName, MAX_PATH);

			if (_tcscmp(szClassName, "#32770") == 0)
				allDialogWindows.push_back(pWndChild);

			pWndChild = pWndChild->GetWindow(GW_HWNDNEXT);
		}

		return allDialogWindows;
	}

The pWnd parameter in above function is pointer to main window in the application i.e AfxGetMainWnd()

I've been stuck on this problem for weeks now and I would really appreciate some insights and opinions.

Supporting Information: VS2019, include afxdlgs.h

Thank you all and I hope you have a wonderful day!

Best,

Aakash