Q: While Lale's e's tend to be high, to my ears she's still clearly singing German long e's (similar to English "ay" with less diphthong, or French "é"), rather than long i's (like English "ee"), in all cases. Your dictionary's pronunciation guide, as you've revised it, confirms what I've said, and all my German dictionaries give one and only one pronunciation for these words, which is as I've indicated.

In any case, if an English speaker sings long i's instead of long e's, it will sound like a clear mistake, because it will be inconsistent with the way he pronounces everything else, and his accent will not support the position that he's speaking "dialect". Unless you really speak like a native, or are singing a song clearly in dialect (such as "I' bin ei Tyroler buah") it's best to stick with standardized pronunciation.