Since I don't know the organizations you have sent letters too and I'm not sure ADPi is one of them, but in the off chance that we are I feel I might be able to give you some information.
AI is still so incredibly new for the alumnae chapters, even though we have been doing it for years. Heck at convention I met a sister who went through AI in the 90's. I was shocked because I hadn't heard anything about AI until about 3 years ago.
Anyways, since AI is still so new some alums just don't really know how to feel or what to do about it. That was actually one of the things we discussed at convention, getting th word out.
Now right now ADPi really would prefer that PNAM's are contacted by an alum/collegiate member not the PNAM contacting EO. I personally see nothing wrong with PNAM's contacting EO to get information, because where else are they gonna get it from, but that is my personal opinion.
But, we do have International Officers whose "job" is specifically AI, so the information would be forwarded to the appropriate sister. I'm sure the same thing happens in the other sororities (where the letter would need to be forwarded to the appropriate person).
Just be patient!!!
I'm not going to say "I know" because I don't know. I don't know what you are going through. I don't know what it's like to wait and wait and wait for a sorority to get back to you. But I do have faith that everything will work out for you.