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Int32MultiArray of pacakge std_msgs is a primitive data type and as such does not contain a header. This is what your error message is telling you.

Typcially, the timestamp in the headers are used to synchronize the messages.

There is a "workaround", however. To quote the wiki

If some messages are of a type that doesn't contain the header field, ApproximateTimeSynchronizer refuses by default adding such messages. However, its Python version can be constructed with allow_headerless=True, which uses current ROS time in place of any missing header.stamp field

See the relevant section of the message_filters ROS wiki.

(Nitpicking: Your question is asking about syncing image and text, but it is actually image and array of ints...)