Will getting a kenalog or steroid shot help this bump after a chalazion excision? Or will 2nd excision be needed? (photo)

A shot of kenalog should be helpful at this point to get rid of the residual nodule.  I would avoid a second surgery. 

It is likely that a kenalog injection would be very helpful here.  I fact, I seldom find kenalog needed because a single kenalog injection resolved the vast majority of chalazia without the need for surgery.  Unfortunately, surgeons sometimes are less inclined to treat these with kenalog because frankly they make more money performing surgery.  

Kenalog sounds like a good option. There was a big study that evaluated the use of steroids and surgery for chalazia. The results are comparable. More interesting, according to the study, regardless of what procedure is done, you may need a second or third injection or surgery to have the stye completely resolve. Patience is important. Consider seeing an oculoplastic surgeon in your area.