These are user to user forums, so not a contact for any Magix staff and no-one here can send you anything!
Which version and edition of Melodyne are you attempting to install? I don't have Samplitude but I do own Melodyne Studio version 5 and it no longer supports the VST2 format, being exclusively VST3.
The installer for my copy of the program is "personal" to me, i.e., it includes the licence file which is directly linked to my personal email address. I'm not sure whether that is also the case for other editions.
But which edition of Melodyne 5? Essential, Editor, Studio? And which exact version of Samplitude?
As I wrote before and certainly for Studio, it is now VST3 only. Can your version of Samplitude run VST3s?
The standard method of "installing Melodyne" is to, quite literally, run the installer! Since it is now VST3 only, the actual .vst3 plugin is always installed to C:\Program Files\Common Files\VST3\Melodyne.