The piece of paper that Dean writes on seems to go through the portal just fine.
As Dog breathes deeply of the humid Amazonian air, a barrage of strong, unfamiliar scents hit his nostrils, making picking up individual scents extremely difficult. However, both he and Dean notice what appear to be path of disturbed vegetation and a series of disfigured footprints in the loamy, grassy undergrowth leading away from the machine and down the clearing.