Here is the sushi.log of my command
sushi -r ~/config_files/config_bp.json # the json file pasted above
GNU nano 5.6 /tmp/sushi.log
[2023-04-21 07:55:03.155] [warning] #############################
[2023-04-21 07:55:03.155] [warning] Started Sushi Logger!
[2023-04-21 07:55:03.155] [warning] #############################
[2023-04-21 07:55:03.282] [info] [main] Setting up Xenomai RASPA frontend
[2023-04-21 07:55:03.291] [info] [jsonconfig] Setting engine sample rate to 48000.0
[2023-04-21 07:55:03.291] [info] [jsonconfig] Setting engine playing mode to playing
[2023-04-21 07:55:03.291] [info] [jsonconfig] Setting engine tempo sync mode to internal
[2023-04-21 07:55:03.292] [info] [engine] Track main successfully added to engine
[2023-04-21 07:55:03.292] [info] [engine] Connected engine input 0 to channel 0 of track “0”
[2023-04-21 07:55:03.292] [info] [engine] Connected engine input 1 to channel 1 of track “0”
[2023-04-21 07:55:03.292] [info] [engine] Connected engine output 0 to channel 0 of track “0”
[2023-04-21 07:55:03.292] [info] [engine] Connected engine output 1 to channel 1 of track “0”
[2023-04-21 07:55:03.293] [info] [jsonconfig] Successfully configured engine with tracks in JSON config file “/home/mind/config_files/config_bp.json”
[2023-04-21 07:55:03.294] [info] [jsonconfig] Config file does not have CV/Gate definitions
[2023-04-21 07:55:03.295] [info] [jsonconfig] Config file does not have any Event definitions
[2023-04-21 07:55:03.295] [info] [jsonconfig] Config file does not have OSC mapping definitions
[2023-04-21 07:55:03.299] [info] [alsamidi] Created Alsa Midi port listen:in
[2023-04-21 07:55:03.300] [info] [alsamidi] Created Alsa Midi port read:out
[2023-04-21 07:55:03.356] [info] [osc frontend] Added osc callback /keyboard_event/main
[2023-04-21 07:55:03.356] [info] [osc frontend] Added osc callback /bypass/main
[2023-04-21 07:55:03.356] [info] [osc frontend] Added osc callback /bypass/passthrough
[2023-04-21 07:55:03.356] [info] [osc frontend] Added osc callback /program/passthrough
[2023-04-21 07:55:03.356] [info] [osc frontend] Added osc callback /bypass/gain
[2023-04-21 07:55:03.356] [info] [osc frontend] Added osc callback /program/gain
[2023-04-21 07:55:03.483] [info] [main] Starting gRPC server with address: [::]:51051
[2023-04-21 09:03:52.304] [info] [raspa audio] Closing Raspa driver.
[2023-04-21 09:03:52.910] [info] [main] Sushi exiting normally!
[2023-04-21 09:03:53.072] [info] [processor] Destroyed processor 2(gain)
[2023-04-21 09:03:53.072] [info] [processor] Destroyed processor 1(passthrough)
[2023-04-21 09:03:53.072] [info] [processor] Destroyed processor 0(main)
Except from the three annotions of missing event …cv …osc mapping definitions
there seems to be no errors, so should the bypass work with this!??