Sorry, but interesting as it may be, it is absolutely not authentic! First of all, the tones we hear in the youtube video are like modern CW tones, albeit lower pitch than we normally listen to. Radio in those days was spark - so the tones were a buzz - Bzzzz Bzzzz. Second, in the first few seconds it says "Titanic to ..." Absolutely wrong! They would not have spelled out "Titanic" in Morse code! The call sign of the Titanic was MGY (I believe the "M" was for Marconi - at that time, the Marconi company ran the wireless aboard ships.) On the Titanic, the radio (wireless) ops were not part of the Titanic crew - they were employees of the Marconi company (albeit they were still subject to orders of the ship's captain).
Sorry to be so critical - good of you to be interested and to forward the link, but I would not want anyone to think that this is an accurate portrayal of what actually happened.
73
Ray