I’m not sure how I can help then. If you have a snapshot pre-v4.1, you can install a prior version of the addon without doing a total system restore. Just unclick all the checkboxes other than Mosquitto.
Not sure if it will help you but the Tasmotta version isn’t always the culprit with connection problems but the core that the firmware is built on. You have a choice between Core version 2.3.0, 2.4.2 or 2.5.0. Each has it’s own set of quirks.
Firmware can be found here.