This sounds like a good exercise, and kudos for thinking differently and at least trying to create a fairer and more useful process.
Two comments I'd make, that I hope you are already thinking about:
1. Role playing is a cringe-inducing experience for many (most?) adults. Please credit the interviewee with intelligence and don't try to actually role-play this. These are hypothetical scenarios, so discuss them as such.
2. As interviewers we are incredibly prone to seeing the things we know as obvious. When you devise an exercise, you can start to believe that everyone should easily see what you consider to be the 'right' way forward. In fact, seeing it may rely on your many years of experience in your company's culture, or your many years of experience with the interview exercise! So please, always remain skeptical of your assumptions about what is obvious, and avoid the trap of expecting candidates to see or follow the path that you think it's best. If any of your support scenarios are actually devious riddles that require one perfect question or leap, then whether candidates 'get it' or not will be random rather than indicative of better performance in-post.
A fire drill where we don't pretend it's real but do take the drill seriously, is fine.
A fire drill where the Health & Safety guy insists that we pretend it's real - yes, most people find this cringe-inducing. For more on this, see Dwight Schrute.
There's a bit of a difference between a fire drill in an office building from the perspective of a regular office employee - and a firefighter. In the latter case it would be expected to have people working as victims complete with mocha[1] injuries and feigned panic.
I don't see why simulating working a bug report need be cringe inducing... If everyone is just playing themselves.
[1] unintentional humor. I suppose there are some unfortunate people that have had to simulate helping someone with a mocha burn or similar injury. I meant "mock injury".
Two comments I'd make, that I hope you are already thinking about:
1. Role playing is a cringe-inducing experience for many (most?) adults. Please credit the interviewee with intelligence and don't try to actually role-play this. These are hypothetical scenarios, so discuss them as such.
2. As interviewers we are incredibly prone to seeing the things we know as obvious. When you devise an exercise, you can start to believe that everyone should easily see what you consider to be the 'right' way forward. In fact, seeing it may rely on your many years of experience in your company's culture, or your many years of experience with the interview exercise! So please, always remain skeptical of your assumptions about what is obvious, and avoid the trap of expecting candidates to see or follow the path that you think it's best. If any of your support scenarios are actually devious riddles that require one perfect question or leap, then whether candidates 'get it' or not will be random rather than indicative of better performance in-post.