It's always a good idea when asking questions about a specific IBA ride to link to the ride page -
To Hell and Back
Within this context - "You must start your SS1000 anywhere, ride to Hell, MI, and return to your starting location." Location can be defined just as it is for the DBR -
DBR - Dated Business Receipt
A DBR is a machine generated receipt with the date, time and LOCATION on it. Check it - do not assume it is correct. A receipt with an incorrect time/date/location is worthless. Check and re-check.
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What this means if if you got a start receipt in Graham, NC at the Shell on Main St, your end receipt needs to also have a location of Graham, NC on it. It doesn't matter if it's the Citgo on East Elm St or from the Bank of America drive through ATM on Pine st across from the Fire Station, it just has to specifically say Graham, NC for it's location. And both are inside the Graham city boundaries. You might get away with the Circle K on E Harden st. but it's not technically inside Graham, even though it does have a Graham address. (zero issue if you used it on both ends)
So to answer your question, Yes it can be the same city. But also Yes, it can mean the exact same location too.
IMHO If you want your certificate to say that you rode from Graham, NC to Hell, MI, then start and end inside the city limits of Graham. (or what ever city you want to use) In the end, it's mostly about the DBRs showing the same city (location). Double check receipts to see how they are printed before you start the ride.