Actually, the compact speaks explicitly—in a proposed action item—about the idea that countries should enter into multilateral, regional or bilateral agreements to manage migration issues.
In objective 23, which speaks to strengthening international co-operation and global partnerships for safe, orderly and regular migration, there is reference to this in paragraph (e) under the action items. It says, “Conclude bilateral, regional or multilateral mutually beneficial, tailored and transparent partnerships, in line with international law, that develop targeted solutions to migration...”
It doesn't say it explicitly, but that's exactly what we're talking about when we're talking about a negotiated safe third country agreement between Canada and the United States.
If you are in favour of a safe third country agreement between our two countries, then you are likely in favour of a compact that endorses not just Canada and the U.S. negotiating that sort of agreement and ensuring that it meets the needs of both countries, but other countries around the world negotiating perhaps similar agreements, or agreements that would be in the best interests of two countries, or a grouping of countries in different regions dealing with their own unique migration challenges.