I dont think you completely understand what constitutes felony tax evasion. Were not talking about typos or math errors, or forgetting to sign your return.
Presumably, they’d prefer to have some kind of smoking gun corroboration, like a “scheme” between two people, or a second set of books, or other evidence that has no explanation other than intention. But your error can still be alleged as intentional, and they have one hell of a bargaining chip when negotiating a settlement of plea.
Any competent tax attorney can take that bargaining chip right off the table. Heck, I could do it. “Show me your cards.”