Since they seem to be based in Kampala, Uganda, they are unlikely to be Afrikaaners (who would generally sing in Afrikaans anyway). I think their renderings are loosely based on a variety of English translations; Psalm 8 seems closer to the NIV, while Psalm 3 has an affinity to the ESV. But their renderings are fairly paraphrased, as is often the case when singing the psalms.