After recreating the table in one of the remote DBs the data has been sent successfully. So, it is a Mobilink issue somewhere.
This is an "upload-only" model, there is no download script on this table, everything is in --{ml_ignore}, so it is highly unlikely that a donwload script causes trouble.
Was your experiment on a table with a small number of columns?
May be you should try to recreate the issue on a table with 60+ columns, like mine.