Why does it say "li'Vnei Merari" without the prefix Vov, and it does not mention a lottery for them, unlike the other parts of Levi?
Malbim (4): Since they remained last, there was no need for a lottery. 1
Dan was the last of the Shevatim to receive, and they received via lottery (19:40)! (PF)
Here it says that Merari received also among Reuven, and 12 cities in all. In accurate texts below (verses 34-37), it mentions only four from Zevulun and four from Gad!
Radak citing Rav Hai Gaon: The cities among Reuven are listed in Divrei ha'Yamim. 1
Radak: Some Seforim were edited to include [after verse 35] verses listing the four cities from Reuven. It is clear from Rav Hai Gaon that they were not in his Sefer! Bi'ur ha'Gra (Divrei ha'Yamim 1 6) points our many differences between the listings here and there. E.g. in Divrei ha'Yamim, all 10 cities of the rest of Kehas are attributed to Menasheh; Binyamin and Efrayim are not mentioned.