I'm going to stick my neck out here because I do not know this author, but needed to get an overview of "The Book of Litivicus":
I watched the video and also took some time to look into the author, Jeffrey Kranz, and his website, OverviewBible.com.
From what I can see, he presents his videos more as educational overviews of the Bible rather than detailed Bible studies. There is certainly nothing wrong with helping people understand the background and structure of Scripture, and I believe he does a fairly good job of that here.
However, there are a few things I think we should clarify.
The speaker is correct that holiness is a central theme of Leviticus. God said, "Ye shall be holy: for I the LORD your God am holy" (Leviticus 19:2). But Leviticus is about much more than ceremonial cleanliness.
For example, the speaker describes God as a powerful being "trying to coexist" with Israel. But Scripture tells us that God Himself chose to dwell among His people. Exodus 25:8 says, "And let them make me a sanctuary; that I may dwell among them."
When discussing Nadab and Abihu, he focuses on ritual purity, but Leviticus 10:1 tells us they "offered strange fire before the LORD, which he commanded them not." Their actions involved approaching God in a way He had not authorized. God's response was, "I will be sanctified in them that come nigh me" (Leviticus 10:3).
The Day of Atonement is another important example. The speaker describes it largely as an annual cleansing of the tabernacle. While that was part of it, Leviticus 16:30 tells us, "For on that day shall the priest make an atonement for you, to cleanse you, that ye may be clean from all your sins before the LORD."
But there is something else I think is important when studying Leviticus, and that is how the sacrifices and priesthood point us to Jesus Christ.
Hebrews 10:1 tells us that the law was "a shadow of good things to come." Hebrews 10:4 explains that the blood of bulls and goats could not take away sins. Then Hebrews 10:10 tells us that we are sanctified through the offering of the body of Jesus Christ once for all.
I realize this is only an introductory video and the speaker cannot cover everything in a short presentation. Still, I believe these are important truths that help us understand what God was teaching Israel and how those sacrifices find their fulfillment in Christ.
So I think the video is useful as a general introduction, provided we examine its explanations against Scripture. As with any Bible teacher, we should follow the example of the Bereans in Acts 17:11 and search the Scriptures to see whether these things are so.