Hasta La Motion!

I’m trying to shoot a scene which basically involves a dolly shot around an empty desk, behind which i want a character to materialize, mid-shot.

my means are pretty limited and i’m wondering whether anyone has any suggestions on the most effective way of approaching this shot. i did think of throwing in an object into the shot, such as a computer screen to briefly obscure the chair, giving the actor time to jump into the shot, but i’d rather have the actor literally dissolve into the empty chair.

is there any way of achieving this without using an electronic dolly? or should i basically try to wing dolly speed / direction in two shots and hope that it matches, and then perhaps try to touch it up in post?

any suggestions would be greatly appreciated!