Don't worry. This response is typical from Rastafarians and anti-colonial based, religious cults. This Rastafarian is only defending his cult according to his own understanding and knowledge, that is why he may seem a little angered.
The problem is the acceptance of Christianity among some of those who were oppressed by so-called Christians. You see, when the Africans were enslaved and brought to this hemisphere, it was done so primarily by European [and sadly, even Eastern] Christians. It is difficult for many African-Caribbeans, African-(North&South)Americans to accept a religion from those who enslaved, raped and stripped their history from them (this is a different subject, but relative).
You are correct that Bob Marley was an Ethiopian Orthodox Tewahido Christian. He was baptized very close to his death, but before that, he advocated the EOTC among Rastafarians. Although a high-population of Rastafarians are in Jamaica and the West Indies (not saying that the West Indies are mostly populated with Rastafarians, as many believe), Rastafarians are not limited to those regions.
Rastafarianism was founded in 1930 after the coronation of Ras Tafari Mekonnen (Haile Selassie I). When an African-Carribbean (not a dreadlock) who was in England at the time heard that Ras Tafari (pronounced: te-fe-ree) was crowned King of Kings, Lord of Lords, Lion of the Tribe of Judah, King of Zion (and so forth); he related these titles with those in the Holy Bible (i.e. Revelation 5:5, etc).
Unfortunately, he was not aware and/or did not make others aware, that all of the Christian kings (or Solomonic kings) of Ethiopia since the anointing of Menelik 1st received these titles. In this case, Ras Tafari used his baptismal name (Haile Selassie: Holy Trinity is my Power) as his throne name.
There are a lot of other legends that were created by Rastafarians to support Biblical evidence that the late King was the Second Advent of Jesus Christ (this is what MOST Rastafarians believe). If you object to one of the Rastafarian doctrines, the answer that you received is typical. Some answers may seem specific, like, "If he is God, why did he deny his divinity?" [Haile Selassie was asked this in the late 60's, because of the cult, expressed his sadness and of course denied that he was far from even a saint].
The typical answer is, "Just like Jesus in the Gospel! He was being humble when He denied his divinity in public, but his children know him!"
Haile Selassie was in a car accident while in exile in Bath, England and he broke his leg. When you inquire about this, because our Lord Jesus Christ did not suffer broken bones, another reply like this may be said, "This is his second advent!"
"What about the Emperor's children?" They may say, "They are angels (or sons of God!"
Most Rastafarians really don't know the speeches or real life of HIM Haile Selassie I, if they did, they would know that His Majesty was a devoted Christian and even advocated many things that they (the Rastafarians) do not advocate.
You may see where I'm getting. If you would like to speak with this or that Rastafarian, the same principles may be applied for other religions or cults. You have to know their doctrine and perspectives. It is of course, always advised to pray and to study the Bible.
I hope that this helped a little.