If you translate it to "rape," you would be committing multiple transgressions:

1. You would be unfaithful to the text, which would be unprofessional.

2. You would be introducing a charge against the defendant that the document does not (within the confines of the fragment that you posted" level against him. Whether you have evidence against him or not is irrelevant. The bottom line is that the document does not name "rape" as a charge. This would confuse the legal case.

3. You would possibly be covering up the gross injustice of the system in the country that produced this document. If this man did in fact commit rape, then a just system should charge him as such. The system in this particular country did not see to it that he gets thus charged. I know a number of countries where such gross injustice does in fact happen. That is very sad, but if you rename the charge "rape," this gross injustice would be covered up, because the system would appear to have charge the man with his crime (if he committed this crime).

4. You would also be covering up the absurdity of referring to a sexual act of a murdered woman as "fornication" or "adultery." Sensible people will find such reference to be disgusting and shockingly absurd. If you change it to "rape," how could the reader know that this system is so shockingly absurd?

The bottom line is that the document uses a word that refers to an illegitimate sexual act, with implied moral condemnation of engaging in the act. The act is attributed to the man, not the woman:

وفعل فاحشة الزنا بها سابقا

Your translation must, therefore, use a word that has the same moral and legal implications, no matter how absurd or unjust. This is the only way to (1) act as a professional translator, (2) expose the absurdity of the system, and (3) expose the gross injustice of the system in the country that produced this document.

Fornication is sexual intercourse between people not married to each other.

Adultery is voluntary sexual intercourse between a married person and someone other than that person's current spouse or partner.

If the defendant is married, then it should be "adultery." If not, then it should be "fornication." Whether the victim is married or not is immaterial, because the Arabic text attributes the act to the defendant.