Torah Temimah cites Toras Kohanim.
“And it shall be for the kohen like the minchah” — so that its service shall be valid when performed by him. A kohen who is the sinner may carry out the avodah of his own flour-chatas.
Diyuk allowing the owner-kohen to officiate — “la-kohen ka-minchah” authorizes the kohen-owner to perform kemitzah and the rest of the service.
A kohen who brings this chatas flour may kemetz and offer it himself. He is not barred from the avodah merely because the offering is his own obligation. The Torah’s language treats the service as valid in his hands.