These are really bad repeaters. There are several community members whose experiences with Cree have been horrible. @april.brandt documented hers in some detail.
There are several inexpensive excellent zigbee repeaters - like Ikea Tradfri control outlets (about $10 apiece). Iris V2 plugs are also popular around here - they work as zigbee and z-wave repeaters. You can often find them on eBay as a lot of 5 for $50.
In the meanwhile, I'm glad your valve is back online.
