My grandsons behaviour is it autism

Hi I need advice from any expert my grandson is 3 and since being very young has shown signs of autism, he has speech delay he can talk better now but still not clear my daughter is having trouble getting him diagnosed  he doesn’t respond to his name a lot of the time especially if in a shop he won’t walk with you he’s very hyperactive he will not let the hairdresser or us cut his hair he screams so bad , he poo smears on the walls/floors and furniture surly this isn’t right , my daughter has got the NHS assessment but all they did is watch him play with toys in the office that obviously he’s going to like because they different to his toys and that was for Half hour then three visits to his nursery half hour sessions and again that’s his regular place so he’s fine there so the assistant doesn’t see anything wrong with him they don’t get to see what we do they just think he needs attention but that’s rubbish he gets plenty they are making excuses I think . I need advice does this sound like autism to other people x