Hi and welcome!
NEC were as bad as Nintendo when it came to region protecting accessories. Technically they can work, but the ports/sockets are either a different shape or have a different pin-out.
In a nutshell, no, the PCE Super CD-Rom wont attach to the US Turbo out of the box. Modding the TG16 will allow it to be attached and work if youre happy to do that.
The more experienced guys here can probably tell you exactly what needs to be done to get it to work.
I have a similar issue actually, but Im looking to get the US TG16 CD unit to work with the PAL TG!