It's possible, but you don't need any admin to explain something that can be easily logically conceived by the average person.
Two possible cases: it is a virus and it isn't a virus.
If it is a virus; the site is designed to let users add submissions. It's entirely possible for a user to accidentally or purposely add a virus, no more need explaining by costello or any other admin.
If it is not a virus; anti-viruses have false reports quite frequently in certain areas of software, no more need explaining by costello or any other admin.
Since both of these cases lead to the same conclusion, my final advice by logic is that, no more need explaining by costello or any other admin.
But I will play with the file to see what it does considering AKAIO is a DS flash cart firmware, what's a virus for windows will not work under the architecture for AKAIO and vice versa
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edit: Why did I put isn't not? ... got to lay off a certain adult substance