Probably correct. HC-05 is a Bluetooth v2 device, and any that purport to be a a v3 or v4 device are likely to be junk. I think it is pretty clear though, that these deices are quite OK so long as you do not want to send AT commands, and most people don't, or don't need to. The latter probably includes you, despite what I said, and reverting to 9600 would be a good idea.
None of the above alters the fact that your problem is unique to you - so far....
I'm surprised you ask the question, as this is surely not a problem for you. Since you are using hardware serial, the monitor AND Bluetooth must match match what you call in your code, which surely you have already ensured. If there is a mismatch, I'm sure you would get much more gibberish out of Bluetooth than the odd extra digit. There should be inverted question marks and all sorts of other crap.