Grandpa Blackheart Beagle = Sherman?

[Larry Giver]

On the last page, panel 2, of Dime & Dime Again, in Gemstone's
October issue of US322, Scrooge demands his #1 dime back from
"Sherman".  The beagle boys are shocked to hear their grandpa
called by this name, since they have always known his name to
be Blackheart.  I've checked the 2 Barks stories (US goes to Disneyland
River race story, and Money Well) and the 4 Rosa stories (Life & Times
parts 2, 10, & 12, and "A Little Something Special") that use Grandpa
or Blackheart Beagle, and couldn't find any mention of another name
like "Sherman" for this character .  So how is it that Scrooge knows
this is his actual name,  while his grandsons don't?
       In this same story, Scrooge's secretary is called Quackfaster in
Part 1, page 4, panel 6, while in Part 2, page 1, panel 2, Scrooge
calls her "Ms. Typefast".  I think Gary Leach posted here that
Gemstone planned to consistently use the name Ms. Quackfaster for
Scrooge's secretary.