Nong Khai to Laos is easy, me mate did it about 2 weeks ago; no issues on her border bounce after having stayed 89 days (60 day TR +30 extension in BKK)
If you're in BKK, after about 15-20 days into your 60 day TR you can apply for the extension, mate.
I understand your desire for the path of least resistance; but I wonder if any IO will concur with what's a work-around solution BEFORE it's done-- after all, you'll likely be in front of a different officer who'll have the discretion to approve or not / require the TM 30; accept that you're staying in some cheap hotel or such. š
Curious of the result if you have that conversation.