Perhaps I misspoke --- the radio (mine) is the Baofeng GM-15PRO. I have 4, actually, and they all talk very well with each other on CTCSS or DCS. I also run a repeater and they can work the repeater too. This is not the problem.
When I try to talk with a buddy - simplex with digital codes/DCS over a range that I have talked with no CTCSS or DCS - 8 miles no problem.
My radio allows me to directly go to a scroll-up/down with a long stack of alpha-numeric titles.
The DCS I've chosen for mine is D754I (that's an "I", not a one (1).
My buddy's TIDRADIOs - (no model available at the mo') - only have as his digital values, things that all end in "N" and he can see: D754N.
They will not talk together although I can hit his squelch as noted by the green light on top of his radio, but the screen never lights up as it would with any other communication going on and he cannot hear me at all - even if he holds his squelch gate open.
I hope I made this clear as I am very confused right now.