The Type broadly refers to the classification of the data stored within your KeePass entry, not the HTML type attribute in the form. Naturally there are overlaps between the two, and that’s partly how Kee can identify which data to fill in where, but you can just use the Text type for “tel” fields.
It’s possible that the solution to what you’re trying to achieve is to force auth-mfa-otpcode to be considered a sign-in field that Kee should fill in. See Including or excluding forms for details about that feature and how to configure it.
If you’re trying to get AWS to work, you might want to read all the gritty details before spending too much time trying to perfect it: AWS sign-in page analysis