Firstly, if the supplier has filed his GST-1 and invoice is showing in your GST-2A, however the supplier has not filed GST-3B
then in this case you don't have to worry, you can take ITC as it is reflecting in GST-2A. It will be vendors headache to pay GST as he has shown liability in GST-1 but not filed GST-3B. Department shall ask from him for tax and not you as he has already filed GST-1.
Also regarding one to one matching of invoices, then the department has put the onus of matching invoices on the dealers. Dealers will have to reconcile everything in their GST annual returns. Also dealers are provided with a tab name "Compare Tax liability " while they file GST returns for every month.
So it's completely dealers headache to verify whether ITC is visible in GST-2A or not, coordinate with the vendors.
It's time consuming and very much complex, but this is the way laws are being drafted and returns to be filed.