NO.  QT breakers are not listed as approved breaker for the G3030 or any other full circuit Load Center. 

He said he can install  a mini(tandem) with a "U" suffix and it would fit. I agreed that yes , they do make QT tandems that would fit in a full circuit designed LC, however they are still not approved for use in that LC. If the breaker frame style is not listed on the panel cover than the breaker type is not allowed for use in that Load Center. Full circuit Load Centers so not have QT breakers listed on the cover.  Use a split circuit Load Center G4224 for example, that will allow QT frame.