The Samanera candidate has already left the monastery and the deputy abbot messaged him to inquire with CM immigration about in-country application of Non-R with visa exempt, but I don't know if he has done so and in all likeliness we won't know until he returns to CM from border/visa run. Either way, I told the abbot that he can do border run to Vientiane if the immigration says in-country application of Non-R is possible with visa exempt, but otherwis go do visa run at Vientiane embassy and apply for single-entry tourist visa as you advised.
What if you don't have a Bai Sutthi yet? I suppose most people applying Non-I Type R outside of Thailand don't have Bai Sutthi for most naturally aren't ordained yet until they land on Thai soil unless they already undertook Bhikkhu ordination at a Thai monastery in their own respective country. Can you be granted Non-R if you don't have a Bai Sutthi yet?
Off topic but speaking of TM30, I see many monks change place of their residence from one monastery to another, especially during Vassa. Many would spend Vassa at a branch monastery or even at temples outside of their own lineage. Some go on to practice thudong and become a wandering monk (often in forest), including foreign monks. Some even dwell in the forest. I don't think you're exempted from reporting TM30 just because you are a phra farang, but I know most don't strictly follow all the TM30 guidelines. Do you have any advice/comment on that?