Hex codes for remote?

Long story short ... I have a Harmony 890 remote made by Logitech.  It controls my Directv HD receiver/DVR, Sony Blu Ray player, Sony CD player, Yamaha home theater receiver, and Sony Bravia TV.  The Harmony remote is fantastic in every way except one ... I cannot get it to allow me to produce a SLOW MOTION command like I can produce on my Directv RC64R remote (i.e. by pressing and holding the play button).  The Harmony will do it only by pressing and holding, then releasing, and then pressing and releasing.  This might be OK except that it only does it about 1 time out of ever 5 tries!

The last email from their tech people said that I needed to "contact the manufacturer of the device and request the Hex-codes. Once you have the Hex-codes, please contact us back with the codes and we will add them to your account."

I called Directv and the only codes they could give me appear to be the codes that are used for telling the Directv remote what model TV you have so it can control the TV.  In other words, the following codes (10810 11317 11685 10011 10834 10111 10353 10080 11904 11100 10010 11925 10505 10273 11962 11641) are possible codes to control the Sony TV.  I think that 10810 is the one to control my Sony Bravia TV, but are these the codes (i.e. Hex codes?) that the Harmony folks are asking for or is it something else entirely?  If something else, where can I get the Hex codes?