For the Mouser BOM it is just necessary to trim down the the 10-pin female header to make it 4-pin. All the 4-pin options were on backorder when the basket was created hence the larger one.
It is easy to cut down the header with wire cutters but requires sacrificing one of the sockets to get a clean cut (i.e. if you want 4 pins, cut in the middle of socket number 5). I've also added a note on this step of the build guide incase anyone runs into this in the future.
Let me know if you have any other questions.