Tissue culture can beat it in some cases because the viroid can be contained to singular branches or shoots, when they test a mother plant they take several cuttings from around the plant to be sure they don't miss it. It is possible to TC a non infected part of the plant and not get hplvd in the resulting clone. Also you can heat treat the propogation plates with the agar in them to sterilize the plant I'm pretty sure.Those kits wont work with this. If it was as easy as simple micropropigation, this viroid would have not become so devastating
The other option is some sort of stem culture they take and do a similar process to, I believe it's called meristem or marestem. I've heard of Joe Ramahi(sp?) Who's one of the guys at dark horse working on this say that it has also been edited out with crispr although I don't know how true that is nor have I really seen anyone else talk about it at length.