Firstly, advice you to buy and connect a USB 2.0 hub and a long USB extension cable to use with Zigbee Coordinator to get it away from EMF/EMI/RMI, see → Zigbee networks: how to guide for avoiding interference and optimize for getting better range + coverage
Secondly, advice you to buy a Sonoff ZBDongle-P (based on Texas Instruments CC2652P) and move to use that Zigbee Coordinator radio adapter instead as the Sonoff ZBDongle-E (which is based on Silicon Labs EFR32MG21) as that only has experimental support in Zigbee2MQTT, and best is to start from scratch again with a new Zigbee network but could try migrating by following this → migrating coordinator from ZBDongle-E to ZBDongle-P · Koenkk/zigbee2mqtt · Discussion #16478 · GitHub
PS: Multi-PAN/Multi-protocol setup has also proven to not be stable with larger Zigbee networks so that is also just experimental.