Luigi's Mansion 2: Dark Moon - Optional E. Gadd Calls

Among the many times E. Gadd calls Luigi in this game, there are a whole plethora of optional calls that usually occur when Luigi deviates from the current mission objective. However, there are some calls in the game that seem to be required, however they can be skipped very easily and without any glitches, which makes them optional to me. Here are plenty, if not all, of the times E. Gadd can call Luigi that isn’t required or needed to beat given missions.
Also, I have made a spreadsheet that contains what mission every optional call play in, what room they play in, how to trigger them, and why exactly they’re optional, so go take a look at that before commenting to ask how one of the calls is optional: https://docs.google.com/spreadsheets/...
Also, please keep in mind that the language in the video is the UK English version of the game, meaning some text will differ from the US English version. The spreadsheet, also, lists every room in their US English versions. If you want to see the translation differences for these calls and plenty of other text from this game, go take a look at this page: https://tcrf.net/Luigi%27s_Mansion:_D...
One last thing: this video leaves glitches and speedrun skips out of the question because most of them require precise movement. I’m saying this because there was a recently discovered skip in E-2 that skips rescuing one of the Toads and an E. Gadd call. It isn't exactly "optional" when you go out of your way to avoid a call.