The existence of rotational flows in solar prominences, also known as prominence tornadoes, has been a topic of discussion for many decades. Projection effects and a lack of spectral information make it difficult to confidently distinguish rotation from line-of-sight motions, oscillations, and counter-streaming flows. Recently a 2.5D numerical model was produced using MPI-AMRVAC where rotation flows inside the coronal cavity were initiated and investigated. For the first time, this work showed the properties and evolution of rotational flows in solar prominences, which are in good agreement with existing observations in SDO. In this talk, we continue working on this numerical experiment by extending our analysis to the spectral synthesis of the Hα line, and several other well-used chromospheric lines using the Lightweaver code and its new prominence synthesis package.