As I understand from
@skyshadow photos two different nozzles can be seen. A larger composite one consistent with that of the composite booster of the Zolfaghar. The smaller one seems to be a smaller metal nozzle that would fit for a SAM such as the Sayyad-4 which needs to be very cost effective.
From the photos I'm not too sure about that but if that's the case then they have tested the Bavar-373 or another LR-SAM against a Zolfaghar.
In that case the LR-SAM went for the booster stage instead for the near-hypersonic glide vehicle (RV).
The S-300PMU2 has 40km max. range against BMs and the S-400 up to 60km. A robust higher PK kill range would probably be 60-80% of that max. figure.
A Zolfaghar would be a difficult target for any ABM system. It has a separating glide vehicle which can perform terminal maneuvers.
Easiest way would have been to test it against a Shahab-1 or -2 with pure fixed ballistic trajectory.
Testing against a Shahab-3 would require the capability to attack and track a 10+ mach target (well within the capability of a electronically steered array LR-SAM system such as the Bavar-373).
The Zolfaghar would be slower at mach 6-8, stay for longer in the atmosphere to be attacked.
Its quasi-ballistic flat trajectory reduced warning time would not affect the Bavar-373 which is limited by its tactical range radar systems.
Using the Zolfaghar as test target would represent an adverse difficult condition for a ABM system due to its separating booster. So the test can be used to distinguish booster and glide vehicle and test the system against two targets with just one Zolfaghar.
Qualifying the system against a maneuvering glide vehicle/RV would be something not even the S-400 is reported to have achieved. Of course the glide vehicle could have been used without evasive maneuvering during a test.
Warhead killing capability is another hurdle which Russians only managed to master well with the S-300PMU2.
Plus: Although we knew it since the Zolfaghar exhibited last year: It has a composite filament booster casing, at least the tested version.