i watched an movie and i heard this:

ya gönül rızasıyla bunu yaparsın ya da ben yaptırmasını bilirim.

Why it say yaptırmasını bilirim and not yaptırmayı bilirim?

i understand whole sentence perfect, except this.

Please someone explain me literaly what it mean.

i wait for explanations

No reason I can think of. I think it´s just that "yaptırmasını bilirim" is colloquial. You´re right. It should have been "yaptırmayı bilirim." If someone said that, that would also be understood. It´s not used as often, though.

It´s like my 5yo nephew asking stuff like: Mom, why do we say ´açık´ but not ´kapatık´?

But you´ve spotted an even subtler glitch. I wonder why anyone would bother to learn Turkish so well

ya gönül rızasıyla bunu yaparsın ya da ben yaptırmasını bilirim.

sounds perfect and natural.

ya gönül rızasıyla bunu yaparsın ya da ben yaptırmayı bilirim.

sounds ok.

i dont know the grammatical difference but here is what i understand:

in the first sentcence, he will make it done to you only by force or by some way.
in the second sentcence, he will make it done to you or someone else.

still there is not a certain line, some other listeners will not notice any difference.

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