Nibbles, 99 8 bytes (1016 nibbles)
?`<+.+.,,$`_$@``p$`_0$``p$
?`<+.+.,,$`_$@``p$ `<>>+. # map over`_0$``p$ , `_0$ # 1.. ,$ get #all lengthsubsequences of arg1 . `_$ # gettingand subsequencesmap ofover this length @``p$ # getting all permutations #of fromeach arg1list, + # and flatten this list-of-list-of-lists, . # now map over this >> ``p$ # getting all permutations of each list, + remove the #first andelement flatten(the thisempty list-of-list-of-lists), `< # nowand sort the list-of-lists, ? # andfinally, get the index of arg2.

