Let's assume the phone had a full range 20-20K. Using my previous example of a truck door slamming at the same time he says the word “cold”.
The vocal range for a male can go as low as below 100HZ and has some content above 4KHZ.
The truck door slam is likely to have content below 60KHZ and some content above 1KHZ.
The question is, using a band pass filter, is it possible to eliminate the truck door slam without effecting the voice content? The answer is no. Reducing the frequency range content of a vowel or consonant has the potential to completely change it.
A consistent “noise floor” can be reduced by adding in a reverse phase of the same content. For example...sampling the noise, when Zimmerman isn't speaking, and flipping phase of the noise and overlaying it onto the "f'n cold" phrase might clean it up some, but unless it's a perfect mirror match, it won't be conclusive.
This all assumes a single audio file.