I think the request is to have capability of automation with standard text input and output decks - for coupled simulations from a third party.
Simulink is a manager for coupled simulations. To it Creo would be a third party simulation solver.
A close equivalent in CREO is called behavioral modelling which can account for CAD variables and internal and external solvers like Mathcad, (matlab competitor). Excel, Creo Mechanism dynamics, and Creo FEA.
Creo behavioral modelling (in Design Study section on ribbon) can perform feasibility, optimization, statistical and multi-objective designs studies (design of experiments).
Also, the inputs and outputs of CREO simulate can be ASCII text based, so with some programming skills, this might be used in third party design study managers and/or coupled simulation.
Creo also has an API license that you can use to automate it with using common programming languages. (Last I knew the API license costs similar to an Creo Engineer III license)
For comparison Altair Hyperstudy is also a design of experiments - generic solver connection software.
Also coupled simulations are done using Python scripts for some solver systems.
Coupled simulation example: For instance an electrical resistive heating simulation coupled to thermal simulation. For this each time step is converged with a loop between the two simulations. The thermal result affects the resistance of the conductors and therefore the watts produced which then affects the thermal result. This is of course assuming separate solvers, indeed some solvers can account for both at once - CFDesign from Autodesk for one.
