wow, either she really misread something or someone told her totally incorrect info. with the PPlus card you can only guest in 2 additional people to the club, and you ARE NOT eligible for upgrades (EUA). you do get the elite access check in and boarding though.
The confusion may stem from the fact that up to nine other people on the same reservation can get elite check in and boarding, and free luggage allowance.(so card holder + 9 friends). If the reservation exceeds 10 people total then you don't get it.