OP:
Does Tony Condon still move glider trailers?

Rail/Ship:
Yes, the trailer should be locked in place by nailed-in chocks and 2-3 heavy ratchet straps.
Every container I've loaded lately had hard points to strap to.
Try a welded steel pyramid-shaped tower with a trailer tow ball on top to support the tongue. Keeps the weight off the jockey wheel and allows you to really tighten the tongue strap in the container.
Containers usually do not get abused but can get moved around far from level, or even dropped.
It's a very good idea to supervise the loading. Sounds like a rough trip on the train for that 20.
Jim