Before revision: We investigate the credit risk model previously introduced by Hatchett and K\"uhn  under more general assumptions . We show that the model is exactly solvable in the N\rightarrow \infty limit and  that the exact solution is described by a message-passing approach outlined by Karrer and Newman, generalized to include heterogeneous agents and couplings.
After revision: We investigate the credit risk model previously introduced by Hatchett and K\"uhn under more general assumptions , in particular using a general degree distribution for sparse graphs. Expanding upon earlier results, we show that the model is exactly solvable in the N\rightarrow \infty limit and that the exact solution is described by a message-passing approach outlined by Karrer and Newman, generalized to include heterogeneous agents and couplings.