A zero fingering in urtext piano music is usually a heads-up that the note is also written for the other hand (as when left and right hand figures coincide on a note), or, as in this case, the note is being held by the other hand and is not to be restruck.

Henle usually makes a general comment (e.g. in the preface) about the fingering (e.g. all was done by the editor) or uses roman and italics to distinguish editor and composer.

The tempo of the piece IMO rules out restriking the note and the way Scriabin notated this is much cleaner and clearer than writing a rest for the left hand.