Not if the engine was as dirty as you have described.
It is essential to keep the air paths clean to allow cooling air to blow directly over the metal.
Oil supply to the bearings in these motors is not the best either and there is always the possibility it was a faulty engine from the start.
if you can do the work yourself then a rod replacement is not a big job, but it is a 3 hour of chargable time job so becomes expensive if the shop does it.