Chip tuning at the TGI (charged natural gas engine) – serious?

Moin together, let’s see if we can discuss here again on the same high technical level as I was used to …. So ….. No matter if I am satisfied with the 81kW and 200Nm or not – is a quantum leap to the 2.0l “Iron Gustav” with 80kW and 160Nm. But he did not have the clearly noticeable starting weakness …. …. but I like to do “self-tests” and have now found a “tuner” that offers 103kW and 220Nm with the TGIs of VW. Now, however, the question arises of how this should be done technically. So, lift charging pressure yes, but with a CNG SRE I lack the technical know-how in the depth. With the Otto DI this is quite “simple”. More charging pressure, higher filling level, more oxygen in the combustion chamber, more fuel, higher medium pressure, finished. But with the CNG SRE this looks different, because both intake air and fuel are already gas-shaped. . If the charging pressure is increased, more CNG would have to be inflated, but what is not possible, because the volume is already taken by the air. Or is this possible within certain limits? Or do I have a mistake in thinking? The “old” TSI TwinCharger was also available with 110kW. Thanks and greetings of the “Stevie”