Don,
If I understand correctly, when you hook either of the mics up in the normal fashion, you get no PTT(?), or frequency control, but it works normally through the Rigblaster? Strange, as I have both those mics, and they work as expected with the FT-847.
The fact that you can work normally in all respects(?) though the Rigblaster indicates that the internal FT-847 wiring is probably ok except for the possibility of the control ground. It is on pin 5. This is really reaching, but is there any chance that the control ground is blown? You can check with a VOM. (A spare 8 pin mic plug is a good way to do this, and tends to reduce the likelihood of accidentally shorting a pin, especially the +5 volts on pin 2 which will blow the series resistor at only 100 ma.) These digital interfaces are often pretty cavalier about separating out the two grounds, and the Rigblaster may be providing the needed ground by combining the two. The schematic, or some quality time with the interface and VOM can answer this.
Probably wrong, but it is at least consistent with the symptoms as I understand them.
Alan WA4SCA