It's only one additional form. I doubt that it will trigger an IRS letter. No one really knows exactly what makes the IRS question a tax return, but there's a lot of confusion about tips this year because of the new deduction. The IRS knows that a lot of employers are not going to do it right.
You could reduce the chances of getting a letter from the IRS by reporting the W-2 as-is and not claiming the deduction for tips. But then you'd be paying tax on all your tips. That's a pretty expensive way of trying to avoid something that might not happen anyway.
Keep whatever records you have of your tips for 3 years, just in case you do get a letter. Would your employer be willing to give you a statement showing the tips that are included in box 1, without actually correcting the W-2? That would help in the event the you do get a letter from the IRS.
