Two errors:

Third line, second matrix: should be a -4 multiplying the 2 x 2 determinant, because the sign associated with the expansion corresponding to -1 has itself a -1, thus keeping whatever sign you had before.

Third line, first 2 x 2 determinant: (0)(-1) - (-3)(-3) = 0 - 9 = -9. You had a +9.

The two errors were sign errors corresponding to the two different pieces, thus totally explaining the opposite sign.