If the P. baroni are adults, the shape of the tail behind the vent will be enough, as in many snakes, the males have bulkier tails, however, lone females may look like males due to the strong and large tail of thsi climbing species, if you wont probe, you need to be able to compare several of them
That said, it is not unusual that when males are handled, they evert their hemipenises
Males will probe to 15-18, females 2-5
I hope this helps,
David