I did even better....I got a lawyer!
http://canonlawmadeeasy.com/2017/05/04/ex-spouse-dies-second-valid/
That means you presumably read he part that says after the death of the first spouse, the second marriage, although initially contracted invalidly, presumably by a civil ceremony (while still married to the first spouse) can THEN be made valid.
"1.) Legally, the second marriage has to be made valid. The Catholic should start by speaking to the parish priest regarding how to go about doing this. Assuming that there are no other canonical issues involved, fixing this should not be an insurmountable problem at all.
Thank you SO much for confirming my point.