I've been doing as much research as I can on fertilizing coconut trees. I've seen numerous people use Salt or Sodium Chloride to fertilize their coconut tree. I was wondering if it is ok to use Pink Himalayan salt to accomplish the same goal or no?

Epsom salt. There's threads on here with more info. 

https://en.m.wikipedia.org/wiki/Salt_(chemistry)

Consider that "salt" is a generic term.

I'd go with Epsom salt in this case.

 

Do coconuts actually need salt? Is that recommended to do or is that just something you can personally give if you wanted too? I've only used palmgain but does salts do anything for the palm?

No, they don't need it. They can simply tolerate it. No need to give the something unecessary to endure.

I put salt in mine, it wasn't that much salt. The palm stayed dormant for a long time and started dying. Eventually it died.

The cause for its death is that the salt had burnt the palm.

According to the book Modern Coconut Management, studies on adding salt to the soil of young coconut plants caused a decrease in nutrients in both the foliage & soil.  Adding salt to yours may mean additional fertilizing to compensate.