I know it looks bizarre but I suppose it may not violate SG2.
A barrel/ball is preloaded by touching the Robot without any contact with the high goal in isolation zone, as shown in these pictures.
I am wondering whether this type of preload could be considered legal.
This is not legal. Let’s take a look at the applicable rule.
The Preload depicted in these pictures, is clearly in a Scored position, if you eliminate the contact with the robot. Thus this is not a legal position for a Preload.