I do not know how the name was pronounced in England, but in the USA I don't think the two syllable pronunciation was just invented by the company. There is a long tradition in English among people with higher education of pronouncing names which come from Greek and which end in "e" with the "ee" sound at the end. Zoe, Chloe, Antigone, Eurydice, Merope, Aphrodite, Psyche, Ariadne, Circe, Daphne, Niobe, Penelope, and Persephone are all normally pronounced with the -ee sound at the end. Irene is the only major exception I can think of; somehow the two syllable "eye-REEN" pronunciation developed for that name in the USA and was later also adopted in England. But I have never heard Nike said in one syllable in the USA.