Enter the 1099-R as you have it. Here is the help article; make sure to expand the sublevels. That includes the Form 8606 (see if your taxpayer included Form 8606 in prior years, for your reference):

https://accountants.intuit.com/support/en-us/help-article/retirement-benefits/common-questions-form-...

"The IRS states the 5 year rule applies from the date of the original owner"

Was this account or other Roth IRA open at least 5 years? There are multiple "5-year rules" for Roth. Having any Roth account at all is the one you noted; and another is Distribution of converted amounts. Each conversion has its own separate five-year period.

"and it was Converted from a Traditional IRA to a Roth IRA in July 2021"

Then if nothing else, there is Basis as of that taxable amount that was converted. Contributions and conversions are basis, because they are post-tax. A beneficiary distribution is an exception to the early withdrawal (before 59 1/2 years old), anyway. Contributions don't have a 5-year rule.

"I know it was an inherited Roth"

You would need to know which of these options your taxpayer decided to use. Perhaps it is a plain distribution-over-time scheme:

https://www.investopedia.com/roth-ira-beneficiary-rules-4770500

"Inherited a Roth" is not the same as "having an inherited Roth." One is a condition; the other is the actual account they opened (if they did this).