For the differences between ResearchGate, Google Scholar and other platforms, see my replies (and replies by others) to:

https://www.researchgate.net/post/Why_my_citations_are_not_seen_totally

https://www.researchgate.net/post/Why_is_there_no_update_of_the_citations_of_my_works_as_there_is_on_Academiaedu

https://www.researchgate.net/post/How_can_I_add_missing_citations_to_one_of_my_publications_listed_in_google_scholar

https://www.researchgate.net/post/Who_stolen_my_citations

https://www.researchgate.net/post/Why_RG_and_GS_shows_different_number_of_citations_for_the_same_article

https://www.researchgate.net/post/What_is_the_best_source_for_h-index

Thank you for providing the links to those discussions on ResearchGate.