Majestic Suites and Majestic Grande are two distinctly different properties.
Majestic Suites is located on Sukhumvit proper between Sois 4 and 6, and, AFAIK, is a love hotel. At night, that whole area is swarmed with ladyboys.
Majestic Grande, on the other hand, is a legit property located on Soi 2 same as the JW Marriott but further down the soi on the opposite side.
Majestic Grande as seen from the JWM 17th floor executive lounge