I have been using K-Lite for orchids and epiphytes 12-1-1-10Ca-3Mg from Firstrays (Ray on this forum) as well as additional GAIA green rock dust (recommended by "Here But Not Here" blog (I wish I knew if the blogger was still active). All I can say is the plants are thriving. I am sure there are many good brands out there.
In addition, make sure you know if those multiflora paphs are of blooming size (old enough to bloom). I think there is some frustration among those who do not realize that these plants do not flower until they are 6 to 8 years old. So up to then, it is just a waiting game. And I feel your frustration. I've bought big paphs off ebay because the original owners gave up waiting. I often think the only time you have a paph that is blooming size is that the breeder knows exactly how old it is (I bought a 6 year old Rothschildianum a month back-- so I know exactly how old it is), or you get a division from a plant that is already blooming size. I personally am not a young thing, so I do not want to wait for 8 years -- so it will cost me a little more money to get something blooming size. (beware the term blooming size also), because a lot of venders who do not also grow, have no idea what that means.