As written it is another nonsense demo claiming to be Vmc. There is no information on other variables which define Vmc eg bank angle, etc, etc.
So, are they trying to duplicate the certificated Vmc or is really just a low speed demo with a satisfactory safety margin?
It is implied that in the specified configuration, at the red line speed, the aircraft is easy to fly, so it may be that it is nowhere near the configuration required for Vmc.
Without a feel for the controllability margin available I can't comment on your question.
However, I certainly agree with the type of work-up recommended.
I don't know what the training system now requires.
As an aside, when validating a Vmc with a manufacturers flight test team, I often flew at the claimed Vmc then conducted a series of engine cuts with increased power settings for each cut until we reached MTP - or a power which was acceptable to do some analysis on.
If static Vmc was limiting then a different approach is obviously required.