Isolation of parameter values admitting heteroclinic orbits in cyclic competition games

Let $(\epsilon_X,\epsilon_Y)$ be a pair of game parameters, and let $Z^a,Z^b,Z^c,Z^d,Z^e,Z^f$ denote the equilibria appearing in the cyclic competition bimatrix game. A heteroclinic orbit from an equilibrium $Z^i$ to an equilibrium $Z^j$ is an orbit whose backward and forward limits are $Z^i$ and $Z^j$, respectively. Isolation conjecture. The set of pairs $(\epsilon_X,\epsilon_Y)$ for which there is a heteroclinic orbit from $Z^b$ to $Z^a$ is isolated in the parameter space. The same is asked for heteroclinic orbits from $Z^a$ to $Z^d$, from $Z^d$ to $Z^c$, from $Z^c$ to $Z^e$, from $Z^e$ to $Z^f$, and from $Z^f$ to $Z^b$. The observation motivating this question comes from parameter values such as $(\epsilon_X,\epsilon_Y)=(-0.09,-0.79)$, where the stable manifold of $Z^a$ and the unstable manifold of $Z^b$ appear very close; whether the corresponding parameter sets are isolated remains open.