Quick resin head question

So a friend of mine is making some armor, and had a few questions about working with resin (or possibly papermache), and I think I know the answers, but I wanted to ask some experts who have worked quite a bit with resin, and this community is one of the first I thought of.

When it comes to resin-based heads, you can spot clean the fur on top, but do you need to be careful (not too much liquid, very gentle brushing/massaging to get the stains out and not let the liquid sink in, etc), or does the resin hold up to cleaning fairly well? In a similar vein, I would think you'd not want to submerge a resin head in water, correct?

And as far as papermache goes, even when treated with a clear coat/polyurethane to make it relatively water-proof, I believe it is still best to not get the finished papermache very wet, and similarly to be really gentle with cleaning, right?

(The main reason for these questions is because the armor might not only be used for a costume, but also for a paint/water gun fun fight in some very muddy terrain, and I'm thinking neither option is the best and it might be in my friend's interest to look into purchasing some vacuum table equipment for herself. Or possibly craft/EVA foam...)

Thank you for any feedback you can provide!