I was serious about pics of the Holly. Trying to help diagnose.
We have 3 of those green giants. Planted 5 years ago and are now about 20-25 feet tall. The last 2 years had the most growth.
As a general rule, the first year after planting a tree they sleep. Second year they creep. 3rd year they leap.
Be patient and make sure in their first 2 years they have enough water coming out of and going in to winter. You want the roots to grow deep, so don't over water, but if we're in Stein in late April or October, give them a few Gallons a week.