Hi Marwan,
Note that this is a case of solar heating with wind effect and cooling via diffusers.
In both the cases the tent is within an external fluid domain with P outlet and conditions as per below tutorial
Assign Temperature Boundary Condition to Environment | CFD 2019 | Autodesk Knowledge Network
The 100 inlet diffusers are within the tent with, and the opening is on the roof as u see in the model and naturally due the flow the air will move out and pressure is applied on the external boundary condition typical to any software even.

For the second case the pressure and temperature at outlet of external fluid is not the issue it is some issue with the software I feel it shouldn't give these kinds of results I tried different open still same issue.
The main issue what I see is the at different levels within the tent along Z direction for 100 DF case the mass is not conserved and is fluctuating, and error is greater than 10% which is not acceptable. Please check how this issue can be resolved I tried even refining the mesh still I had the same issue.
Please check this.