right before 42b you wrote (Beraisa - R. Akiva): "The owner of the ox is clean" from the 30 Shekalim for killing a slave.
I don't know how accurate it is to say 30 shekalim when the gemara says demey eved ( i think theres a ketzos that discusses demey eved is something separate from 30 shekalim)
also believe a type at end of 42b you wrote
Question: R. Akiva says aid(my comment:over here ) so (that he does not inherit them) even about damages (that are paid in her lifetime)!
1) Baruch she'Kivanta to the discussion of the Rishonim here! The Shitah Mekubetzes cites different opinions on this matter.
(a) He writes in the name of Rabeinu Peretz that in this case "Demei Eved" means the 30 Shekalim. However, he adds that some explain that he is even exempt from paying the value of the Eved. According to the latter Pshat, he is exempt from the Demei Eved, and Kal va'Chomer from the 30 Shekalim.
(b) The Re'ah maintains that "Demei Eved" means specifically 30 Shekalim.
In short, the more simple explanation is that "Demei Eved" here means 30 Shekalim because this is the fixed value that the Torah gives for the Eved.
2) I agree that there is a typo at end of 42b. It seems it should read "Rebbi Akiva said so." In addition, the bracketed words "that are paid in her lifetime" do not seem to be correct because the Gemara discusses what happens if she dies. It seems that it should read: "Rebbi Akiva said so (that he does not inherit them) even about damages!"
Thank you for pointing that out!
Kol Tuv,
Dovid Bloom