Definitely not Oleaceae. Swollen petiole base suggests it is a compound leaf. Is this the max height? Do you have images of open flowers? Also do you have images of stipules or fruit?
yes i agree it is not oleaceae. yes 40 cm is max. height observed among population. The flowers open this much only, i have some other views and closeup which i will add here no fruits were found. stipules image is not present with me.