Encouraging some roth roots?

[The Mutant]

So, one of my two very expensive Paphs, the rothschildianum, came with a very poor root system. As a matter of fact, both the rothschildianum and the Michael Koopowitz had practically no root system at all, but the MK did have some root nubs going and something that looked like the beginning of a basal fan, and after a week in my care these root nubs have started to develop into real roots and the possible basal fan has swelled considerably.

On the roth however, no such thing is happening and I wonder what to do to promote some root growth on it? I'm going to give both of them seaweed extract like all of my chids get and this I've understood that it does have some root promoting abilities, but will it be enough?

Also I'm wondering whether or not I should keep it a bit dry to promote some new root growth, as one should do with Phals?

Finally, I'm planning on adding some seaweed extract to the water I'm using to spray the sphagnum daily with, this also to promote some root growth. What do you guys think about this? Is it a good idea or a bad one? I've sphagnum as top layer on all of my Paphs to keep the moisture a bit more even in the pots and to prevent any possible root nubs from dying from dehydration. This is working wonders on my Paph roebelenii for example and I was so happy to notice that it actually works (I recommend this to all of you Paph newbies out there!) that I'm continuing doing it. So, good or bad idea to add some seaweed extract to the spraying water?

Here are some photos of the Paphs in question. The first two are of Michael Koopowitz and the other three are of Mr roth and its lack of root nubs.