So I figured out my fix, instead of just letting Blizzard take charge of the Tooltip Header Font I added this line to cTooltip.lua:
Code:
GameTooltipHeaderText:SetFont([[Interface/Addons/cTooltip/Media/Expressway_Rg_BOLD.ttf]], 18, 'THINOUTLINE')
And now it doesn.t change anymore.
Coke