For free? Well, with Orochi it were only three people who were TECHNICALLY able to do the job (seal demonic creature). But their bloodline were backed up with their skills (according to KOF:Kyo, Kyo isn't the only one with flames in his generation of his clan, just the most skilled one) so they had not only tools but the ability to work with it. Without it, they would have been most probably dead.
With Ingiz was the same stuff...he was pwnd by a group. But remember one fact...normally storylinewise it's the champion team who meets the last boss (fights with Krizalid and Ingiz happened AFTER Hero Team was declared champions, they didn't have to beat them in order to become champions) and except 2003 the hero team always was the champion team. So Kyo KOing Krizalid doesn't counts too much as stealing thunder from K' since storylinewise his team was already declared champions when they get to that underground base.
Sometimes (normally at the end of the saga- with Orochi and Ingiz) final fight happens in form of free-for-all thing. But that's almost always AFTER the actual winner is declared.