When it comes to the politics there is a lot of guesswork involved as we don't know what horsetrading is really going on behind the scenes. But consider:
Both the Libs and Nats need each other to form government, but the Libs need the Nats more than the other way around. Without the Nats the Libs are in perpetual opposition. Sure, the Nats get a seat at the table via the coalition, but they're generally fed crumbs and are tolerated as a necessity, not a desireable partner. We've got the spectre of Barnaby Joyce quite possibly rolling McCormack in the very near future and becoming - and it pains me to write this - deputy PM again. What a time to be alive.
But anyway. Whatever else he is, Joyce isn't backward in coming forward and if pulls off a coup then the first thing on his agenda will be to assert his authoritie. He's going to want more power and influence for the Nats, and what will have just happened? After standing up numerous times publically to support the government's position, and the concepts behind the Advent project, one of the few ministers that they do have, one of the crumbs the Libs have offered them, gets overruled just like that with an off-the-cuff comment out of the blue from the PM. What's the point of having ministers if your coalition partner can just go "yeah, nah" over their decision-making whenever it is convenient for them? I can't see Joyce happy about Pitt being thrown under the bus, especially since they are both birds of a feather when it comes to resources. Not only that, but Pitt got the bus treatment in a complete about-face of the governments long and often stated position of a gas-led recovery. He must be feeling like a right monkey now - he's been pushing the line and making the right noises since he got in, and then suddenly *crunch*. Thanks for nothing.
So the Nats, and Joyce in particular, won't be in any hurry to grant the Libs any favours. I doubt that the Nats would split the coalition, as Joyce likes his seat at the table too much, but they can create enough noise to get the possibility firmly on the front pages and also on the lips of every journalist at every press conference that Morrison turns up to. What better issue for Joyce to beat up the PM about? Reversing a policy direction, a resources policy at that, and backstabbing one of his senior colleagues to do it. You think Joyce cares if Sharma retains his seat?
Add to that the current problems that Morrison is trying to deal with. He's used up, and using up, a lot of political capital to save his ministers from scandal. I doubt Morrison is any danger of being rolled, but there's an election coming sooner or later and you can bet there are some ambitious Libs looking at the possibility of a solid election win based on a "we got Australia through Covid" campaign. Being the recipient of that would be a tempting pot of gold, and while it might not realistically happen the threat of it would be very much there. It doesn't take much rumour for our media to start leadership speculation, and that's a snowball that is hard to stop once it gets rolling. An annoyed National party who wanted leverage over the Libs could do worse then threatening to start destabilising Morrison's grip on power.
For those kinds of reasons I don't think the PEP approval is necessarily dead in the water. There's more wheels turning in the background that we can possibly know, and the directions those wheels might turn is anybody's guess. Give Morrison the choice between offsiding the Nationals and having to give ground to them, and offsiding some greenies in safe Liberal seats, he's going to choose the option that keeps him in power, even if that means eating a bit of public and private crow. He's going to need to do that in any case, so he might as well try and come out of it as best he can.
(20min delay)