On Pharaoh's not knowing יקוק
Jacob and his sons, when speaking to Egyptians, consistently refer to God as (ה)אלקים, "the god", and not by his name, יקוק, that distinguishes him from other supposed gods, or other names of his. (E.g., Genesis 39:9, 40:8, and 41:16–32 passim.)
(When speaking amongst themselves, although they usually use (ה)אלקים, they occasionally use another name. E.g., Genesis 48:3, 49:18.)
Later, Moses and Aaron tell the pharaoh (not the same one as in Joseph's time) that יקוק had said to release the Jews. (Exodus 5:1.) The pharaoh replies (5:2):
Who is יקוק that I should listen to him? I don't know יקוק and won't release the Jews.
This sounds to me possibly like he's tying the two together: like, had he indeed recognized יקוק, he would released the Jews.
I wonder whether any commentators tie these facts to one another: that the pharaoh didn't know of יקוק because the Jews had never referred to him as such. I wonder, too, whether any go so far as to say that, had Jacob et al. used the name יקוק, the later pharaoh would've let the Jews out on demand.