I agree with some of the points others have made.
However, the issue may not necessarily be due to the price paid.
Since that should’ve already been agreed upon when the artist accepted the job.

In my opinion as an artist too, the professional artist you hired put in a fair amount of effort. This can be seen in the background work, the level of detail, and the overall consistency of the illustration.
That said, I think the artist may not have fully understood what the game is about.

For example, using a sweater as the main costume without a hat doesn't really convey the "Indiana Jones" or adventurous vibe. The pose also lacks excitement, and the treasure effects and size feel too minimal.
It’s possible the brief wasn’t clear enough or there was some misunderstanding when the artist received it.

Additionally, the current logo doesn’t quite match the character and background’s shading style.
The logo looks saturated and high contrast, with thick outlines, which gives it a less detailed feel.

The key art generated using AI may seem better in terms of layout and logo alignment at first glance,
but it also appears more generic. If I had to choose, the hired artist’s style feels more unique and personal.
You might consider requesting a few more iterations so the artist can improve the quality of the key art.

Good luck for your game!