the relay outputs on the msc400 don't have voltage on them.  you can run voltage though them, but it won't be necessary in your case.

you will just take apart the switch like you have done already, then solder onto the contacts where the up and down buttons are.  use thin wire such as cat5 for this purpose.   you will end up with 4 conductors which will get connected to relay 1 and relay 2 on the msc400.

the up button would get connected to relay 1 using the Com and N.O. connection.

the down button would get connected to relay 2 using the Com and N.O connection.

in the programming you would just pulse the relay for half a second to send the tv lift up or down.  the relay closes, which in turn acts as if the button on the keypad has been pressed.