Historical Context

[ReneZ]

it is possible to solve this problem not with interpretations, but with scientific evidences only

A good piece of evidence would be the following:

1) take a known plain text in the language that you are proposing.
2) convert it into Voynich MS writing using your rules
3) demonstrate that this result shows the known properties of the Voynich MS text.

If this works, then your theory should be taken very serious.
If it doesn't work, then you have to be able to explain why, and this will be difficult.

If it is not possible to find such a known plain text, then this is a bad sign.
At least some cognate language should exist.
If that is also not the case, it is a very bad sign. You are postulating the existence of a language, and we can no longer speak about evidence, but only about hypothesis.

It might even be that step 2 does not work, but we can skip that complicated point.

The most important properties of the Voynich MS text are the typical word structure, and the very limited combinations between characters, which can be expressed in a number called 'entropy'.