How is this not an excellent opportunity to develop your character further? While I have admittedly no idea who your character is outside of being Angel Cartel, your reaction to this mistake suggests that you do not view your character (regardless of all her other faults) as the sort who would naturally have faked an autopsy for the sake of a Public Relations/Political Capital gain.
I'd say Play it straight - Lie through your teeth IC: That body is totally legit, nobody saw anything to the contrary, she's a liar, and anyway screw the rules, you have money!
If you make sure your opposite is aware of this OOC you can both play with it for a while and then maybe draw out the zomgScandal of your character's vile deception, or muddle the investigation and make it ambiguous as to which body is the real one. Or in the end, she eats the real body and whoops, looks like your autopsy is the only one left, giving you benefit of the doubt.