If you try again, do you get the same behaviour every time? The strange part is that it fails with a timeout, but when you look closer at the timestamps, there is no sign of a 3 second timeout. The entire session lasts only about 1.5 seconds.
Are you able to download a full memory dump?
dctool.exe --family ostc3 --model 0x3B --verbose --logfile dctool.dump.log dump --output "dctool.OSTC4.bin" COM17