Basically, the parallel plan is chosen if its cost is lower than the cost of the serial plan.
The thing is the parallel plan's cost is calculated a little different, so most likely the serial plan's cost is higher than 95.
Here's two options:
1. Run the query with option(maxdop 1). That way you will know the serial plan's cost.
2. Raise the cost threshold for parallelism to a very high number and start lowering it until the parallel plan returns, and it will give you an idea of the serial plan's cost.
Hope it helps.