what is meta id for this

I am using a plugin to push products from my main site to a child site. I have an option to insert product metadata ID keys in this plugin’s settings so when I sync products to child site, it also syncs the metadata.

Previously I had input “pwd-brand” as the meta id and it was working great, child site would receive the brands from master site sync…after latest update it is not longer working.

Please advise.