@Paulo i found what the problem was. I decided to check why Appsmith and Superblocks were connecting without problems, but Retool was having trouble. It turned out that they simply had SSL enabled by default.
Example Appsmith
And at Retool it is necessary to switch it on separately and requiring to add files for some reason, which confused me, as we have not done it in other cases at any time.
Ended up just selecting Full verification and it was successful. I think you should pay attention to this in the guides, as your solution didn't work even with a direct AWS IAM import.