This probiotic can be ordered in bulk from Korea. It is often used in food processing. It’s Korean manufacture has some other rare probiotics which I will look at in the future. It is also available in Spain with Bifidobacterium longum.
Pediococcus is a Firmicute, which is the phylum that CFS/IBS/FM patients are too high in. This does not exclude it — but raises the bar to require known benefits.
Microbewiki describes it as
“Pediococcus pentosaceus are categorized as a “lactic acid bacteria” because the end product of its metabolism is lactic acid . Pediococcus pentosaceus, like most lactic acid bacteria, are anaerobic and ferment sugars. Since the end product of metabolism is a kind of acid, Pediococcus pentosaceus are acid tolerant. They can be found in plant materials, ripened cheese, and a variety of processed meats. Pediococcus pentosaceus is industrially important due to its ability as a starter culture to ferment foods such as various meats, vegetables, and cheeses. Pediococcus pentosaceus bacteria is being cultured and researched for its ability to produce an antimicrobial agent (bacteriocins) as well its use in food preservation …P. pentosaceus can produce an antimicrobial agent known as bacteriocins  “against several species of Lactobacillus, lactococcus, leuconostoc, pediococcus, staphylococcus, enterococcus, bacillus and listeria””
- Adding another lactic acid produce is usually not desired because lactic acidosis is common with CFS/IBS/FM.
- The antimicrobial agent it produces may be too widely targeted (kill the good and the bad).
The Known Science
- “combination of probiotic agents (Pediococcus pentosaceus, Leuconostoc mesenteroides, Lactobacillus paracasei, Lactobacillus plantarum)…. demonstrated that probiotics increased mortality, in part because of the precipitation of ischemic bowel disease (in patients who were also receiving postpyloric enteral nutrition infusions).” 
- Septic Shock Secondary to a Urinary Tract Infection with Pediococcus Pentosaceus. 
At this point of time, it is not recommended. It definitely has benefits in the food industry to stop spoilage. It has a very wide range of antibiotic action against both good and bad — and run a risk of doing more harm than good.