If radial is fine, then your 1x should be fine too.
But, why did you do 100% outbound spokes, rather than alternating inbound/outbound.
Ahh, interlacing vs no interlacing??
It may not make a difference for a vertical load wheel.
Hmmm...
https://bicycles.stackexchange.com/q...on-traditional
Spokes in a crossed pattern are usually interlaced at their last crossing before reaching the rim. Spokes coming from between the flanges are laid over those from outside the flanges. Interlaced spokes take up each other's slack during severe radial loading and reduce the chance of spokes becoming loose. If spokes become loose, their nipples can unscrew. Radial spokes cannot be interlaced and therefore, lose alignment from road shock more easily. Interlacing also gives more clearance between the spokes and the derailleur on rear wheels.
So, the idea is that if you apply rotational torque (pedaling/braking) to the hub, then the interlacing straightens the pulling spoke, thus pulling the lax spoke slightly, and helping maintain even tension.
That really won't matter for your trailer.
If you've already built the wheel, then I don't think I'd worry about it. It'll be fine.
Note, many of the 2-wheel trailers also dish the wheels outward to give them a slightly wider stance.