From my point of view, it helps to know who you are and how long you are staying; however, I can confirm that this hotel does not have any suites attached to the SPG3SU rate plan. This means that the suites are outside the standard suite category, which are used for Platinum elite upgrades.
The best you can do here as far as room type is the Deluxe room category. These appear to be junior suites. For what it's worth, changing to a club level room would definitely be a downgrade in room type from what I can tell.
I have a problem with your being denied club lounge access, however. I suggest this: Go back to the front desk. Ask them for your Platinum amenity of choice card. While you are filling it out, ask them again for club lounge access. If they refuse, tell them that they will be hearing from Hotel Customer Service tomorrow if they don't give it to you. Then let me know what they say to that.
Best regards,
William R. Sanders
Specialist, E-Communications Department
Starwood Hotels & Resorts Worldwide
[email protected]