Hello youngman, and welcome back to the community!
Thank you for both logs and helicorder screenshot. From them, it appears that the booting and connection processes are fine, with the Shake finding an internet connection and synchronizing its time with the servers.
However, these lines in the logs, tell us that there is something going on between the boards and the sensors:
2023 237 09:05:57>> ÑEI ÉÊ1œE
2023 237 09:05:57>> S ÁS ÑÊQŒDI
2023 237 09:05:57>> 15892 503
2023 237 09:05:57>> No Data has been received from the MCU in 14 read attempts.It appears the MCU is not transmitting data. This is a fatal condition and should be investigated if this condition persists!
2023 237 09:05:57>> Data has been successfully received, fatal condition resolved.
As you can see, there are errors mixed with some ‘gibberish’ that cannot be successfully interpreted. My first thought would be to check and see if the power supply is delivering a stable voltage between 5.0 and 5.2V and a current of at least 2.5A at all times, as a decrease in power could lead to data services interruption. If you have another Pi power supply that you know is in working condition, please try to exchange the current one with that, and see if the Shake now properly boots.
A second check that you can do is to see if all the connections between the sensor, the blue Shake board, and the Pi board are still solid and free from dirt or any other element that could compromise transmission. This is important, in particular, if the Shake is located in an environment where dust or moisture can affect it. If needed, you can find assembly guides here in our manual: Assembly Guide — Instructions on Setting Up Your Raspberry Shake
When doing this, please make sure you are using proper ESD (ElectroStatic Discharge) protection (such as gloves, etc.), as electronics do not like static electricity too much.
If all these checks come out as positive, then I would recommend re-burning the microSD card, and see how the Shake behaves with a freshly-installed system. I will leave the burning instructions here for your convenience:
Thank you for your collaboration!