To me, Helaina in particular is not a phonetic spelling. You could pronounce it like Helena, but also Hel-line-a, or Helannah.
To be honest, if I saw it written down, my first instinct would be Hel-ai-ee-na.
When people are confronted with a name spelled they haven't seen before, they won't have a clue how to pronounce it. Some will just read it how it might be phonetically in English. Others will assume it isn't an English name (because if it was, it would be spelled Helena), and so they will try and make sense of the spelling in a context of any other similar names they know - including non-English names. So then there will be a whole load of other possibilities for pronunciation thrown into the mix, that wouldn't be there if you had used a standard spelling.
Having said that, my DC is bilingual and has a name that is popular, or at least well-known, in many european countries, spelled in a standard way. It is pronounced differently in her two languages; when speaking language A, she is known by the language A pronunciation, and when speaking language B, by the language B pronunciation - even within the family. They are both "her". It is like she has two names, and she genuinely seems to not mind, and think it completely natural that her name should be pronounced two different ways.
So personally, I wouldn't get too hung up on different pronunciations, but I know lots of people would think differently.