"A country that had so much potential, until an unbridled dictator took the reins. They never recovered"
Not strictly true. The economy has been growing at 4-5% each year for a few years. The problem is the rampant corruption, which is, according to the UN, the worst in Asia. This is not Marcos' fault but the fault of successive presidents. The last president, Arroyo, is widely considered to have been the most corrupt of all, even more than Marcos.
This means the poor look to religion for hope, and the JW's, as just one amongst a colony of religious vultures, are there for the easy pickings.
Do not think these numbers are all that high, however. This is a country of 90 million, so 200 000, probably including any kid over 8 who goes out with mom door to door, is a tiny number. Religions there normally count members in the millions.
Door to door activities alone do not count for growth amongst JWs there. Compare LDS Brigham Young University Newsnet quoting senior missionary Dave Brinsfield: "Out of the 49,000 converts who joined the church in 2001 and 2002 [in the Philippines], only 1,000 remain active."