Replicación Master / slave - MySql
Find the flowchart that explains what happens when you have a mixture of binlog_do_... and binlog_ignore_... -- it is not necessarily what you would expect.

Be aware that

USE db1;
INSERT INTO db2.tbl


uses db1, not db2 for determining whether to replicate.

Which binlog format are you using?

For further debugging, use mysqldumpbinlog to see if a particular row was inserted into the binlog file on the Master and/or whether it arrived in the relay-log file on the Slave.