Looks fine to me. :) Just to point out, "she's greeting you" - Present tense. "she's greeted you" - Past tense. :)

All of those could be used in different contexts, yes. If you are with someone who doesn't seem to understand what a person is doing or saying, either because they didn't hear or they don't understand the language, you might getting their attention or explaining, "She's greeting you." If someone seemed to ignore another person or didn't remember meeting, you might say to them, "She's greeted you twice now." Maybe you don't recognize someone and you ask your friend, "who is that?" Your friend might reply, "She greeted you when we got here." In a similar situation at a repeated event, "She greets you every time we come here and still you don't know her?" Hope that helps.