Will my roommate’s late share affect me?

Rent split between roommates is not reported at all, so no.

From the guide Rent-Payment Credit Reporting.

What is never reported

• Rent split between roommates.
• A lease with a payment plan for rent the resident could not pay in full.
• Rent part-paid by a housing program — Section 8, a housing voucher, CityFHEPS or any other subsidy.
• A business lease. Only household rent is reported.

Those leases are listed on the resident’s screen with the reason, so nobody wonders why a month did not appear.

Read the whole guide: Rent-Payment Credit Reporting

More questions about Rent-Payment Credit Reporting

• Is my rent being reported right now?
• Can a late payment hurt my credit through Seayora?
• I paid by Zelle. Does that count?
• I pay my rent in cash. Will it be reported late?
• My lease says my rent will be reported. Can I opt out?
• Does rent reporting cost anything?
• Why is my month not on my credit file yet?
• Can I stop later?
• As a landlord, can I see whether my tenant reports their rent?