Wjkk, wjkf,
I don't know why is their so much fuss abt all the god referred names in Sri Guru Granth Sahib Jiji. Is Raam name was coined for the King Raam only? was there no word like raam before King raam got name raam, same goes for other names like vishnu, brahma, krishna etc... do anybody even prove that these name were never ever existed before these.
What I think is that these names had some values associated with them which is more important then looking at the name. I think their was word Nanak existent before Guru Nanak's parents named him Nanak.
Reference:: Sikh Philosophy Network http://www.sikhphilosophy.net/hinduism/22557-sikhism-hinduism-and-sanatan-dharam.html
Sabat da bhalla