That's indeed a mistake: in that structure, neither 'looks like' nor 'seems' like will work. Only this is possible: '...a manikin that...seems/looks very human.' (No 'like' is possible there.)
'Seems/Looks like' takes a clause, not a prepostional phrase:
It looks like / It seems like it's going to rain. ('Seems like' is very informal; 'looks