OK, I've done a bit more testing and have verified that FLDigi has no problem keying the SCU-17 but direwolf is having problems.
If I set FLDigi's Hardware PTT to /dev/ttyUSB1 RTS then I can trigger PTT with tune. If I turn tune off PTT is let go.
DTR gives me FSK properly
RTS = +V gives me a PTT dead key
DTR = +V give me a FSK dead key
If I set direwolf to...
PTT /dev/ttyUSB1 -RTS
I get a FSK RTS dead key
RTS gives me a FSK dead key
DTR gives me a PTT dead key
-DTR gives me a FSK and PTT dead key
This has to be a config issue I'm missing somewhere
Edit: Just did some digging, seems I'm not the first to have this issue....
https://github.com/wb2osz/direwolf/issues/44
