It is strange that she does not have reliable travel agents in her city or area. In SPB or any large city there are reputable agents that will prepare the visa for her. Hope that helps.
That is very strange. My fiance is going to an agency in Yekaterinburg to obtain her visa. I do not know about SPB. I know she needs to go in person and apply, and then return to pick it up when it is ready. Hope that helps you.