The link above shows the 10 largest factors ever found with P1 (if the file is up to date). Only 3 of these were found with prime95/mprime.
Factors found with p1 above 39 digits are rare (although i'm convinced many more will be found if more time is spend running P1 compared to ECM).
If it takes 1 minute to test for 6 missing digits it will take about 190 years to test for 14 missing digits.
I't might be faster to rerun P1 with high memory limits to see if the factor can be found again.
