@Boone, have you tried using the Gradient filter? You can take the gradient of a vector field and get the 9-component second derivative. The Gradient filter is also capable of secondary values (such as divergence, vorticity, and Q criterion), which you can turn on with the advanced values.
If that does not work, like @Christos_Tsolakis said, you can make both derivatives available in your pipeline by simply connecting the d1u filter to the d2v filter. This will make the outputs of both available at the same time (as long as you have unique Result Array Names, as @Christos_Tsolakis also said). You could instead combine the output of the two calculators with the Append Attributes filter, but @Christos_Tsolakis’s solution is easier.