NO, you're correct.
The language the lady wrote was "obsolete" i.e. she was using language the persona couldn't comprehend. It didn't mean she was speaking like, Arabic or something - she was still speaking English.
The Heritage House, to me, was about journeying and forgetting your past/roots. Even when the persona tried to go back to it, she couldn't understand. Same applies to those who abandoned the house when the government cut funding. So yeah... you could tell that the persona felt alienated because she couldn't comprehend the significance of the items in the Heritage House (lol a technique I used here was 'accumulation of nouns': BOXES. PAPER. WAX...). Also, the symbolism of the home was significant too.