I'll answer my own question.
Hi Welby :) thought I’d tell you the back story on the cover of Africa Cos I LOVE Weezer :)
The reason Weezer covered Toto’s “Africa” was because of an online twitter campaign to have them cover the song which was started by a teenage girl. The campaign gained a lot of followers and attention, they only covered the song to basically troll the girl back lol. I thought it was funny and in good humour on their part. They didn’t change the song up though Cos was a last minute recording...
Also in turn, Toto covered Hash pipe by Weezer.