validate_nwb_slap2.py fails to plot data due to formatting mismatch in recent experiments

The validate_nwb_slap2.py script is currently unable to correctly generate plots for specific experiments (e.g., [776270](https://allenneuraldynamics.github.io/openscope-community-predictive-processing/experiments/allen_institute/slap2/allen_institute_776270_2025-07-02/) and [801381](https://allenneuraldynamics.github.io/openscope-community-predictive-processing/experiments/allen_institute/slap2/allen_institute_801381_2025-06-05/)), despite being expected to parse this data.

It appears that the data format within these specific NWB files differs from what the script currently expects, leading to parsing errors and missing plots.