Pedagogy; Gentile Slaves

I finished Volume 1 of Joseph Telushkin's A Code of Jewish Ethics, and I started Volume 2. I have two items.

1. In Volume 1, I was reading about Jewish pedagogy, which included such issues as the expensiveness of Jewish day schools, the importance of encouraging students to ask questions, how a prominent rabbi was upset when a student regurgitated what the rabbi said about the text the day before rather than offering his own opinion about what the text means, and how angry and impatient teachers discourage learning. Telushkin wonders about what happened to Jewish students who had dyslexia in a time when no one knew what dyslexia was. How did they cope in an environment that valued academic accomplishment in Torah? Did they leave Judaism on account of impatient teachers?

2. In Volume 2, on page 47, there was some discussion about Gentile slaves. Deuteronomy 23:16-17 says that the Israelites are not to turn over a runaway slave to his master, but the slave is to be allowed to dwell among the Israelites. As Telushkin notes, this differs from how slavery was applied in the United States, for the 1857 Dred Scott Supreme Court decision mandated that slaves fleeing to the North be returned to their masters.

Telushkin discusses the interpretation of Deuteronomy 23:16-17 by Maimonides and Onkelos. Maimonides, in "Laws of Slavery" 8:9-10, "understands this law as applying to a non-Hebrew slave belonging to a Hebrew master who wishes to move to Israel" (page 47). I don't have Maimonides' book, so I don't fully understand what Telushkin is saying here. Who wishes to move to Israel: the Hebrew master or the non-Hebrew slave? Regarding Onkelos, Telushkin says that it interprets Deuteronomy 23:16-17 "as referring to a non-Hebrew slave of a Gentile master who flees to Israel." That makes a degree of sense. In any case, both interpretations probably hold that the passage is about a Gentile slave who seeks asylum in Israel.

This stood out to me because the laws on slavery in Leviticus 25 assert that Jewish slaves are to be released at a certain point in time, whereas Gentile slaves can be held forever. It was interesting, therefore, to encounter Jewish views on slavery that actually valued the well-being of Gentile slaves.