Try using these solver settings (these will be the default in v4.2.0) for poroelasticity without a fault:
[pylithapp.petsc]
pc_type = fieldsplit
pc_fieldsplit_type = multiplicative
pc_fieldsplit_0_fields = 2
pc_fieldsplit_1_fields = 1
pc_fieldsplit_2_fields = 0
fieldsplit_trace_strain_pc_type = bjacobi
fieldsplit_pressure_pc_type = bjacobi
fieldsplit_displacement_pc_type = ml
fieldsplit_displacement_ksp_type = gmres
Information available on the fault surface is limited to values that are available on the fault. When prescribing slip, this includes the slip and the change in tractions. Note that PyLith v4.1.3 contains a fault orientation bug the gives erroneous results for the tractions. Refer to Fault orientation bug in PyLith v4.1.3 (and v4.0.0-v4.1.1) for more information.
If you want the traction and fluid pressure at the location where a fault is (without having the fault), then use the material output and compute the fault traction from the stress tensor, making use of the fault orientation. This will need to be done as part of the post processing, such as in a Python script.