You need to stop talking about policies you don't understand.
Net zero is a national commitment. Not some hard and fast rule. It does not in any way mean every hydrocarbon consuming activity has to stop in 2050. It means that whatever is consumed will be offset. On the list of emissions that need to be offset in 2050, VIA Rail is very, very, very far down the list. We can talk about cutting VIA's emissions when auto and air emissions in the Corridor are cut substantially.
Exactly. VIA will never be able to dictate technology use on networks it does not own. And my bet is synthetic biodiesel is easier to adopt for most North American railways.
The only place where electrification is really relevant is the Corridor. And even there not all services need to be electrified. If the bulk of intercity services are on an electrified HFR Corridor, which could easily be London- Quebec City by then, the vast majority of riders will be on electrified services.
The real challenge is cost. If a fuel substitute for conventional diesel is not found, we may end up in a situation where VIA fares are something like 5-10x the variable cost of driving an EV. At that point, electric buses and cars are very likely to kill all passenger rail service that is not electrified and not heavily subsidized. With the declining price trends for EVs and the increasing prices for carbon taxes, we may see this well before 2050. I would think VIA needs to start working on a switch now to complete it by 2035-2040.