[Note: I ended both problems early due to length]

?- consult('cryptoexh.pro').
%  combosets.pro compiled 0.00 sec, 7,504 bytes
% cryptoexh.pro compiled 0.00 sec, 11,112 bytes

Yes
?- crypto(1,2,3,4,5,6,A).

A = ex(ex(1, +, 2), *, ex(5, -, ex(3, +, 4))) ;

A = ex(3, *, ex(5, -, ex(ex(1, +, 2), +, 4))) ;

A = ex(ex(ex(1, +, 2), *, 4), /, ex(5, -, 3)) ;

A = ex(ex(3, *, 4), /, ex(5, -, ex(1, +, 2))) ;

A = ex(4, /, ex(ex(1, +, 2), *, ex(3, +, 5))) ;

A = ex(4, /, ex(3, *, ex(ex(1, +, 2), +, 5))) ;

A = ex(ex(1, +, 2), *, ex(4, /, ex(3, +, 5))) ;

A = ex(3, *, ex(4, /, ex(ex(1, +, 2), +, 5))) ;

A = ex(ex(1, +, 2), *, ex(4, +, ex(3, -, 5))) ;

A = ex(3, *, ex(4, +, ex(ex(1, +, 2), -, 5))) ;

A = ex(ex(ex(1, +, 2), -, 5), /, ex(4, *, 3))

Yes
?- crypto(7,7,7,7,7,7,A).

A = ex(ex(7, +, 7), -, ex(7, +, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), -, ex(7, +, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), /, ex(7, *, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), /, ex(7, *, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), +, ex(7, -, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), +, ex(7, -, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), -, ex(7, -, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), -, ex(7, -, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), /, ex(7, /, ex(7, +, 7))) ;

A = ex(ex(7, +, 7), /, ex(7, /, ex(7, +, 7))) ;

A = ex(7, +, ex(ex(7, +, 7), -, ex(7, +, 7))) ;

A = ex(7, +, ex(ex(7, +, 7), -, ex(7, +, 7)))

Yes
?-