Hmm… This is a problem, but at the same time, I feel like there’s a reason for it:
If this card is Synchro Summoned: Increase or decrease this card’s Level by the Level the Tuner used as material had on the field.
The wording on Cupid Pitch’s 1st effect assumes there is only 1 Tuner. Sure, she does not specify there has to be exactly 1 Tuner for her Level change to reference, but I am fairly certain that does not mean the game does not get confused over which Tuner’s Level to reference, even if both Tuners had the same Level…