Ramban explains that when Moshe Rabeinu said to the elders to go and get the lambs for the Korban Pesach, that they had to travel all the way to Goshen where their flocks were.

Throughout the discussions in Torah and commentary we hear that the Jewish people were in Goshen.

And at one spot we hear that during the plague of the death of the firstborn that Pharoah went to Goshen searching for Moshe and Aharon, but they were staying near Pharoah's palace - (presumably in the capital city?).

If Moshe had called the elders to this capital city location, I can see how the elders themselves would have to travel to Goshen to both tell the Jewish people about the Korban Pesach, but then they and the people would already be in Goshen, where the flocks were.

So I can still justify an assumption on my part that for the most part, perhaps with this encampment of Moshe and Aharon near Pharoah, that the Jewish people were in Goshen, except perhaps while working in Pithom or Ramses or any other work location.

And I would summarize this as that the majority of the Jewish people were in Goshen.

But Ramban's comment would be more consistant with the majority of the Jewish people not being in Goshen, and having to travel to Goshen to get the lambs from their flocks.

Perhaps this then is a source for the (under-emphasized) principle that actually there was a majority of the Jewish people lost in Egypt during the plague of darkness -- some say 4/5th of the people died.

Particularly if insular communities help preserve Yiddishkeit, and we know that we had fallen quite low in Egypt, perhaps there was in fact a majority of the Jewish people who had left the insulated community of Goshen, and this contributed both to their being not redeemed, and having to travel to Goshen to get the lamb for the Korban Pesach?