There are no distinctions in the rules for host vs. non-host skaters/teams for getting replacement events when they withdraw from their assignments . There are two explicit statements about Non-Seeded Skater/Couples, in 2.2 k and l:
"k) Non-Seeded Skaters/Couples will not be invited to another event in replacement if they choose not to skate in an assigned event.
l) Non-Seeded Skaters/Couples will not be invited to another event in replacement if, by medical reason,they withdraw from an assigned event."
In section 3.4 (Obligation of Seeded Skaters), I think it is implicitly stated that there won't be replacements for seeded skaters/couples (emphasis mine):
"Seeded Skaters/Couples who agreed to participate in the ISU Grand Prix of Figure Skating Series andSkaters/Couples who qualify for the ISU Grand Prix of Figure Skating Final must skate in their assigned events and in the Final." There are provisions for withdrawals.
Of course, that never means they'll follow their own rules, which include needing to sign off on all replacements, but that's what it says.
It doesn't address skipping a potential assignment from the alternates list, ie, if they can choose to skip one and stay on the list, because there's a financial obligation for the skater/team's fed to pay the difference between the cost and host "travel contribution" for more than 14 days before the event and to pay for transportation in full within 14 days of the event. The hosts can get sign-off for not replacing skaters within 7 days because of travel, visa, or other hardships, but they aren't on the hook financially. For the invited skater/team's fed, they might, for example, want to not send their skaters to an expensive destination
if they can skip it and be assigned to one that is cheaper. It isn't clear what happens if an invite is declined, and if that depends on the reason given, if any.
The incentive is still to throw host spots back into the pool within the 14-day mark, especially now that they have to pick from the top of the list instead of the bottom to avoid competition for its own skaters -- they no longer have to subsidize other skaters to beat their own -- but it takes away the financial obligation to subsidize travel expenses within 14 days, and they may not care about the competition if their skaters are likely to be stronger or at the bottom of the pack anyway.