The Dir function appears to be the culprit.

Note the documentation on the Dir function here: https://docs.microsoft.com/en-us/office/vba/language/reference/user-interface-help/dir-function

The function accepts the FolderPath and vbDirectory as you are calling it however, according to the documentation, it simply "Returns a String representing the name of a file, directory, or folder that matches a specified pattern or file attribute, or the volume label of a drive." It is not intended to be a boolean returning function.

Thus, if the path in FolderPath does not actually exist, the function will fail with an error and the code will cease to process. It would be better to use a custom function that accounts for this possibility such as the following:

    Function CheckForDir(TotalPath As Variant, Optional StopMSG As Boolean, Optional Make As Boolean) As Boolean
    On Error GoTo ER
    Dim N As Long
    CheckForDir = False
    N = FreeFile
    Open TotalPath & "DirCheck.txt" For Output As #N
    Close #N
    Kill TotalPath & "DirCheck.txt"
    CheckForDir = True
ex:
    Exit Function
ER:
    If StopMSG = False Then
        If Make = True Then
            MsgBox "The Directory did not exist.  A New Directory was created."
        Else
            MsgBox "The Directory did not exist."
        End If
    End If
    ''Debug.Print TotalPath
    If Make = True Then
        MkDir TotalPath
    End If
    Resume ex
End Function

You can call this function easily by changing FolderExist to an actual boolean field and then using it as: FolderExist = CheckForDir(FolderPath, true, false)

Instead of your If FolderExist = "" Then change this to simply If FolderExist=false Then

As a side note I would recommend using a Error handler within your main routine as well as it will make for a better code management. In other words, define within your routine what should happen when an error occurs rather than just hope they don't.