He said part of one of those names. Now assuming that it isn't just the letter J in all of them, that means that literally any part part of the names could be used. We should start trying variations on the first few letters of them instead of just changing a letter or adding a suffix.
-Jam
-Jad
-Jar
-Josh
-Jere
-Jeff
-mes
-den
-ed
-shua
-miah
-frey
I'm not saying to mix and match them, but if we could find enough names with those in them, we'll be on to something.
