From the description mentioned I understand that looks like you have found an error where you are sure that transceivers which are not supported are mentioned in the optics guide for model 7550 and 7650.
I ran through the details you mentioned
From the above details mentioned in optics guide looks like there is firmware requirement for 7550 and 7650 to support 25G optics .
Since its mentioned as 2 for both 7550 and 7650 it is supported only after 10.0.0 or later
Could you please help me with firmware version you are running on the switch ?
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