Best way to translate 见闻 in a sentence
见闻 is a noun word in the context, meaning "what one sees and hears; knowledge and information". Interpreting as "experiences" in this context is ok I think.

Your statement is correct:


  "since the lyrics are usually given with a linebreak after 见闻
  (jiànwén), it might be that 见闻 (jiànwén) is actually another noun
  going with 热吻 (rèwěn) to be the object of 赠 (zèng). "


Small tweaks on your translation 2: "You gave me too many experiences [and] warm kisses that couldn't be taken away."