No stable equilibrium problem

Stochastic simulations
1

I modified the mod file of the stock-Sir model on Github, but got the following error feedback: Blanchard & Kahn Conditions are not satisfied: no stable equilibrium.SIR.mod (1006 Bytes)

3

Is it obvious that the model has a unique saddle-path solution back to steady state when you linearize it? After all, the dynamics around the initial steady state should be explosive.