The only help I can offer, is a link to the inhao's product download site for LCD_2000_7775 which includes a .rar file with support files incl. libraries for your display.
I read the instruction but there was no obvious hint how to hook the display to a teensy, only for Mega2560 and Uno. Maybe somebody else with the same hardware configuration might assist you further on.
You could also search this forum with keywords "teensy lcd_2000" - then you might find previous or current discussions going on with similar or same issue.
Good luck.