@LumberDavid Not really much of a solution, but you can get intervene plus the epic RE "Temple Guardian" to remove their weakened soul debuff, putting it on yourself instead. With 2/2 Safeguard talent and possibly some "hasty intervene" green enchants to reduce intervene CD, it could even half-work.
If you don't want to run all dungeons like that though, you'd have to burn a spec slot for this modified version of your build.
Here are two more sane solutions:
Keep another healer spec on a secondary spec that you can use when your tank is Crimson Championing. Get a premade tank (that you know isn't a Crimson Champion) to run your dungeons with. As an added bonus, you'll get more instant pops, because DPS are aplenty.