Yes. The chronology is something like this:
1967: goes to Thailand as a Peace Corps volunteer.
1969: ordains. I’m not sure where, but in the ordination photo it looks like either a village wat or a down-at-heel provincial town wat. It’s too decrepit to be a Bangkok wat and since he’s holding factory-manufactured robes it’s not likely to be an Ajahn Chah wat. After ordaining spends a few months with Ajahn Chah at Wat Nong Pa Phong.
1970: hears about Mahāsi-style vipassanā and becomes interested. Ajahn Chah gives him permission to go off and practise it. He then spends a year in intensive practice with the Burmese monk Āsabha Sayādaw at Wat Vivekasom in Chonburi. Āsabha (b. 1910) was a disciple of Mahāsi who taught in Thailand from 1952 until his death in 2010. In Path with Heart Kornfield writes of him:
After studying with my first teacher, Achaan Chah, who was impeccable in conduct, in many ways a model guru, gracious, insightful, and loving, I went to study with a famous old Burmese master for a year-long retreat. He was a grouchy old slob who threw rocks at the dogs, smoked Burmese cigars, and spent the morning reading the paper and talking with the loveliest of the young nuns.
In private interviews he was a very fine teacher. After training thousands of students, he truly was a skillful guide to inner meditation. But when I saw him in other situations, I became filled with doubts, thinking, “He couldn’t be enlightened.” It took weeks of inner struggle before it dawned on me that he was a great meditation teacher but otherwise a poor role model. I realized that I could take what was beneficial and not buy the whole package. I didn’t have to imitate this man. Then I became rather fond of him. I think of him now with affection and gratitude. I wouldn’t want to be like him, but I’m grateful for the many wonderful things he taught me.
After his retreat he then went around visiting most, or possibly all, of the Thai teachers covered in Living Buddhist Masters and wrote a sort of Baedeker Guide to their monasteries (published by the World Fellowship of Buddhists in 1978) He also paid a short visit to Wat Nong Pa Phong, during which there occurs the well-known episode where he tells Ajahn Chah (some accounts say Ajahn Sumedho) of all the wonderful things he’d experienced during his retreat and receives the reply, “Just more to let go of.”
1971: goes to Burma, takes a new ordination at the meditation centre of Sunlun Sayādaw. Stays there a short time and then goes visiting most, possibly all, of the Burmese monks covered in Living Buddhist Masters.
1972: returns to Thailand, though I don’t know where or for how long, and later to the USA. Then some time between 1972 and 1974 he disrobes.
1975: Wat Pah Nanachat is founded.