I think you have done your part. Especially if you are considering (or have decided) to shut down in May. (hope I am not confusing posters?)
You have highlighted your concerns and now it's really up to mom and dad to take it further. Some things sound normal, some not so much. But it does seem a little too early to tell for sure.

On side note: Lord, how I HATE baby talk!!! I mean, or family has a few silly words, like skettis for spaghetti. But I am sorry; "Is that the wall?" should not sound like "Izzat da wawww?". It's entirely possible that this is why mom can "hear" the words, but you cannot. Ughhh.
On the other hand; my second boy was just about 3 before anyone outside the family could understand what he was saying. Sometimes it comes harder for certain kids. In retrospect, the fact that he ended up needed an adenoidectomy later may have had something to do with it?