Impedance of current probe
Like you say, the required output imedance doesn't seem to be mentioned in the manual (or both of us can't read), but they say you can hook it up to a multimeter with a BNC-to-Banana adapter. I am not aware of any multimeter with a 50&nbsp;Ohm input impedance, so I guess the porbe's output is a voltage buffer designed to drive a device with a high-Z input like a multimeter or a 1&nbsp;MOhm scope input. (If this was not the case, you'd get readings that would be wrong by about a factor of 2.)

Also, the corner frequency of the probe is 100&nbsp;kHz, which doesn't really require a defined 50&nbsp;Ohm transmission line with termination.

So no, I don't know for sure - but yes, I think 1&nbsp;MOhm with some pF in parallel is most likely the correct answer.