The British brought a lot of people from India into their colonies in Africa and elsewhere : https://en.wikipedia.org/wiki/Indians_in_Kenya#Kenya_Colony and it's not implausible that this would be an origin for the term.
Many Old Bantu words such as mti for tree are in Swahili. similarly sounding words are used in languages from west Africa to South Africa (muti, miti).
From India, we have Pilau, chapati, dhania...
http://www.rahmahmuslimhomeschool.co.uk/index/wp-content/upl...
http://www.languagesgulper.com/eng/Bantu.html
https://en.m.wiktionary.org/wiki/Category:Swahili_terms_deri...