I suspect the prepositions in this lesson don’t mean the same in US and British English.
As a Brit, I wouldn’t say either stop by or pop by somewhere. Pass by and go past mean the same as each other and don’t imply you stopped or went inside: for that, I’d use "go", "pop" or "drop" "into" or "in to" or another construction like "I went to see Laurent at his house".
So I’m not clear if "Elle est passée chez Laurent" means she went in to see him or went past his house without stopping?
(Setting aside the usage of "place", as in "Laurent’s place")