Questions 1 and 2 - Yes, TurboTax does provide a method by which you can adjust your CA income to reflect that portion of your ISO which should not be taxable by CA. You may have to calculate the ratio, and the links that you provided in your post provide examples of how a CA non-resident can determine the portion of their ISO that is subject to CA tax.
When you have determined the amount that is subject to CA tax, you can then enter that amount on your CA return. The numbers from your federal return will populate your CA return. As you go through the CA section, you will see a page such as Here's the income that CA handles differently, or a similar page. That will be the page where you can enter your ISO information.
If you don't find an option that matches your situation exactly, on that page there will be a Miscellaneous category, with a sub-category Other Adjustments to Income. You can enter your adjustment there.
@Herbert570
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