ok, hier steht alles
https://aeroexpress.ru/en/aero/press/news20101355.html
Tickets will be issued to fans via Aeroexpress ticket offices two days prior and two days after the match date, as well as on the date of the game upon the provision of corresponding documents. A ticket to one match gives the right to no more than two rides in a standard railcar.
also ab zum schalter und ticekt holen, online geht es scheinbar nicht