I see. Disregarding the fact that it won't stain as well, is there any harm if in staining and finishing the wood after just a week or two? Will the internal moisture content be an issue? Great idea with doing another set of branches. Another thing I'm thinking of doing is just building the tree as is and letting the branches dry out on their own indoors, then I can decide if I want to finish it at that point.
In terms of the marks, it's definitely for me not the cats . I consider the piece I plan to build to be a decoration as well and feel like all the marks give it a bit of an unnatura