I was able to get it to work with the following code:
% Forms matrix to hold data
Master_temps = zeros(numel(Cure_Kinetics.neat(1).iterated.temps), number_of_data_files)
% Compiles all neat iterated temps into one master matrix
for i = 1:number_of_data_files
Master_temps(:,i) = Cure_Kinetics.neat(i).iterated.temps
end
% Places master matrix into data structure
Cure_Kinetics.neat_model.compiled_temps = Master_temps
