Until recently gas was a waste product because we had no way of shipping it offshore. When you bought it you were basically paying for the infrastructure/delivery not the gas.
Now we have gas terminals and ships to cart it and the price overseas has gone up we're being sucked in to world parity pricing again (we know from experience how that ends).
The seam gas in mines isn't straightforward to capture. You either extract it after it's diluted with air or you interfere with the main game, shearing off coal to sell. Gas has a value but it's not that high yet. At some point it might become economic, but I don't think we're there yet.
I have never worked for a mining company, I worked in research and testing for the coal industry for some years. I am not in any way beholding to them, and it would never shift my opinion on anything. I will say I won't identify my current employer. They are imbeciles, but they are vindictive vengeful imbiciles, and I'm not quite ready yet to get sacked from this circus. I would never defend them though :) I just don't like some of the misinformation spread in propoganda so I perk up on coal to set the record straight from time to time. I'm equally ready the point out their sins, like f'ng coal seam gas mining....
Hope that clears it up.