Space can be a problem, for sure. Just so my comments are understood, they are meant to hopefully help you with the problem, and not to be taken as being hypercritical.
Your first shot was at 24mm focal length, and the distortion is obvious.
The second is at 70mm and very little distortion is noticeable. It seems also that the camera is more level in the 2nd shot, and you are shooting slightly down on the first one. That is probably because you are farther back, on #2. Since you are farther back, even if the camera is at the same height, it is not as noticeable, due to the distance from subject to camera. So much for all that.
The white background is 5 feet wide? Whatever the width, you must have had to extend it in #1 (using Photoshop).
I can see the item in the foreground is some sort of a wall or partition, and you may be shooting through a doorway, in #2. I guess taking it out would be a problem; however, you can also just clone out the foreground. I don't believe it would be much more PS work than what you are doing to extend the background. So if you can shoot from the same distance as you are in #2, you will be able to eliminate the distortion on full length shots.
Just some suggestions. My first "camera room" was about 12' x 12', and that was before digital, so removing any foreground was expensive.