So, if there is a talk a round, it would be the same freqs as the system?
Not necessarily.
If you look at the FCC license, you'll see at least two entries:
FB2 (or some other number), that'll be the repeater OUTPUT
MO, That'll be the repeater input and those can usually be used in simplex mode.
So, look at the license, and try plugging in all their MO frequencies and see what you hear.
Some license for -just- a simplex frequency also, so there may or may not be an FB2 attached.
If you told us who you were trying to hear, we could help you find the license.