The motor might bounce around on the desk a little, but without a prop I wouldn’t be too worried about it.
I’d be careful with those spliced power leads on the battery though. If those aren’t very solidly attached, a tug could pull those wires apart and cause the positive and negative to touch. With a battery that big, that could cause a good sized fire. I’d strongly suggest carefully soldering the XT60 into the leads directly and eliminate that splice. One side at a time though! I wasn’t thinking one time and snipped both wires together and it took a couple seconds to register the burning hot sensation in my hand that was holding the battery. 😂
If you absolutely can’t solder, then maybe at least drop some super glue on the spice to hold it in place? Also, heat shrink tubing. I’m not sure that this would work, but it would be safer than wrapping the wires in tape only.