I checked to confirm the appropriate behaviour of the OMC_DCPD filter banks. When TIA is set to 100, FM8 should be on and FM9 should be off, and vice versa for TIA set to 400 (see figure 2). However, there was no change in the filter banks when I changed the TIA setting.
I tried replacing the switch in figure 3 with an AND gate (TIA_ZSW_OUT AND CONNECTED) but it didn't make a difference. Then I just removed the AND gate, sent CONNECTED to a terminator and put TIA_ZSW_OUT into B7 and B8, with the NOT gate still before B7. But that didn't make any difference either.
When I change the TIA setting in the OMC dock I can clearly see a change in the output signal of the DCPD, and using caget I can confirm that TIA_ZSW_OUT is going between "ON" and "OFF" (or 1 and 0 if using ezca read). So I guess the problem is somewhere between the model and the interface.