I don't think the issue here is so much that the front wheels are off the ground. I have lifted my front wheels on occasion myself. But when I have had to lift the front wheels the procedure was to raise the front jacks until the motorhome was level. And then lower the rear jacks only until they touched the ground and took a little weight off just to stabilize the motorhome. But the OP also said the site here is level and the motorhome is not. So there doesn't appear to be much reason to have set the motorhome up like this.