that's why I said you were so lucky for your Friendship poem met a talented translator

晕，好像明白你想说的了，不过你补充的英文表达，尤其在后一个that's why，晕乎乎。

修改：that's why I said the English-Chinese translation is much better than I expected and that's why I said you were so lucky that your Friendship poem had met a talented translator.

其实就是修改一个地方，不要for，为什么非要for呢？直接so...that结构不好么？“这就是为什么我说你是如此的幸运，（以至于）你的"友谊诗"遇到了一个好翻译”---你是这个意思么？

如果非要用for,那就that's why I said you were so lucky for your Friendship poem having met a talented translator。用一个现在分词的完成结构。