The hotel page mentions an AC lounge, but I found that a bit strange so I tried digging deeper.

I first tried chat support, who claimed the brand was "boutique hotel". When I inquired what elite benefits members received, they said they couldn't help me because my account has a PIN and asked me to call in.

I called in and the agent claimed the brand was "Marriott". However, she also said it didn't have a lounge and wasn't full-service which sounded strange to me. Finally, I asked her how many points you got for the welcome gift. This got her to dig a little deeper, and I think I finally found the answer.

She mentioned the "Milan Hotel Group" which I was able to find a website for. On their site, it mentions the hotel is in-progress to convert to an AC hotel.