The part does not exist in Mecabrick part library, yet. It has been requested in this thread several times(I'm missing it too for some models). https://www.mecabricks.com/en/forum/topic/50

Unfortunately it is more or less only Scrubs who model parts and add them to the library so the list of requested parts is quite long.

Oh this is bad news. Also i can suggest to make the import feature work how it should be because i foudn that part in Studio.io and in LeoCAD, exported, and then tried to import in Meca but i cant see it in the viewport. And I cant import .DAE in meca.

Because it's not in mecabrick library it will not be imported. Mecabricks does not import the 3d geometry from other software, it converts the models to mecabricks parts, so if some parts don't exist in mecabricks library they will be missing from import. Scrubs could surely give you a better answer with more details about the import but that's basically how it works.