The parameters

tcp-initial-timeout (25 - 1200)
tcp-idle-timeout (1 - 1200)
tcp-keepalive-timeout (1 - 65535)
tcp-advertised-timeout (0 - 65535)

... have documented valid ranges (shown above in parentheses).  The tests should be extended to check that the specification of out of range value causes BIND to emit a warning and adjust the value to the appropriate boundary.