The test is not complete. Checking only 20 of the 24 variants, I easily pass all the tests. Here are the sides I verified (side-by-side recordings):
[ '1243',
'1342',
'1546',
'2134',
'2431',
'2536',
'2635',
'3124',
'3421',
'3526',
'3625',
'4213',
'4312',
'4615',
'5263',
'5362',
'5461',
'6154',
'6253',
'6352' ]
As I understand it is the case when the cube turns 90 counterclockwise. But I just can not think up examples to close this gap.
Created at: Sept. 29, 2018, 3:31 p.m.; Updated at: Oct. 11, 2018, 4:09 p.m.