Joe, I think I can help out with a couple answers. I’ll work from last to first. Yes you can add an Emerald Ring in series and control whether it is ‘in circuit’ or not. I would not advise using the power source as a way to control the ER, but rather allow it to remain powered and bypass the signal with a DPDT mini toggle, if you don’t want to put it on a footswitch. Either is possible. For a toggle simply wire the two end pins at one end of the switch together with a jumper. this will be the bypass direction. Then wire the In and Out pads of the ER to the 2 pins at the other end of the switch. This leaves the middle two pins available the ‘In’ side goes to the Angry Llama and the ‘Out” side goes to the out jack. The switch will either direct the signal to the board or avoid it. Keep it powered though to avoid pops and noises.

For the Angry Llama, since I have to guess, I’ll say that the pot values were possibly mixed up. There are other guesses but you really should take the time to provide some clear photos of the front and back of the board and include some of off-board wiring. Do the testing without the ER being involved. Test it separate if any issues. Many extra eyes always helps.