I have successfully used the TK2374 probe with the 2382/2380 spectrum analyzer.
I was confused when trying to understand the power connections through the auxiliary cable, but it does work.
I measured the THD (at 500 kHz) of the combination, using a Wavetek 98 generator driving 0 dBm into a 50 ohm termination (either the SA input or a terminator at the probe input):
Direct With 2374 probe
Fundamental 0 0
2nd harmonic -63 0.07 -37 1.4
3rd harmonic -61 0.09 -46 0.5
4th harmonic -70 0.03 <-72
THD 0.12 1.5
dBm % dBm %
At 0 dBm/50 Ω = 0.22 V rms, the distortion of the probe is predominantly 2nd harmonic, with a total value of 1.5%. The DDS generator itself is quite clean, despite being at one-half its maximum frequency. The bandwidth of the probe (50 Hz to 200 MHz), should not matter at this frequency.