Plant Identification (Psidium Sartorianum?)

[shmojojojo]

I bought this second hand from someone on craigslist a few years ago. It had a tag from Mimosa Nursery (called, no help) and hand written on the other side was "Arrayant". There are a few plants called Arrayan, so I was hoping to get a proper identification from some pros, or one of you guys It's flowering for the first time this year. Hopefully it fruits so it can help with identification. I think it's Psidium Sartorianum/Sartre Guava, but I see a lot of misidentifications with that plant. Some with golf ball sized fruits, others with berry sized. What do you guys think? Also, does anyone have any advice for the yellow leaves/green veins? Is that a PH problem? Nitrogen or iron deficiency? Thanks.