Is it a tautology or not? According to my truth table its not
The question is not phrased clearly.  Perhaps the question can be rephrased as follows: Let $p,q$ and $s$ be propositions whose truth values belong to some subset $A \subseteq \{T,F\}^3$.  Suppose $A$ is such that $(q \leftrightarrow p) \leftrightarrow s$ evaluates to true for each assignment from $A$ and $p \rightarrow s$ can take both possible truth values over assignments from $A$. Can $q \rightarrow s$ take both possible truth values over assignments from $A$?  

But there are many $A$'s which satisfy the given two conditions, and different $A$'s will give different answers- it can be a contingency, or it can be tautology.