Jean,
I guess there's no
way to know if GIO has rec'd my invite.
As Bruce said, there is:

If that grey box at the top of the In Process page says
they have, they have. Otherwise you'll need to re-send. Wait at
least a few hours since your latest send to give it time to
register on the page.
One reason you might need to re-send is if you originally sent the
invitation before having competed Step 1. Sending the invitation
is Step 2.
Shal
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