A properly functioning TVS diode appears as an open circuit until it's breakdown voltage is reached. Having them in parallel shouldn't be an issue with one exception.
The capacitance of a TVS diode is significant in some circuits, especially if you have the higher wattage ratings. The 36V models we frequently specify have around .001uf capacitance for the 1.5KW rating, that could easily affect some circuits. Obviously, for multiple TVS diodes, you add them up in parallel.
The capacitive reactance of .001uf at 3.27 mhz is less than 50 ohms, a few of those across the DCS signal would likely impact the signal strength, something to consider.
