Hello,
I just did what you suggested and saw where the problem is coming from.
There is a group, that I created myself only a few months ago, that is dated to 31/05/10, about seven years before. I'm not sure how it happened though that this group is set to 2010 when it was really created in 2017? It was also given ID 4, while recent groups have ID's around 20. It's as if it somehow confused the new group with an old one (that was probably deleted quite some time ago) and it took the creation date of the old group with the same ID for the new one - at least that's my guess.
Of course, given that date, it is normal that the module doesn't display it among the "latest". So the problem is not with the module but with something in GroupJive itself.