"To [the best of] our knowledge, no writer anterior to the [period of the] Reform utilized the symbolic imposition of sins on the scapegoat [at Lev 16] to illustrate the Pauline paradoxes of 2 Cor 5:21 and Gal 3:13, according to which, on this interpretation, Christ would have become sin personified, malediction itself."
Léopold Sabourin, S.J., "Le bouc émissaire, figure du Christ?," Sciences écclesiastiques 11 (1959): 69 (45-79). "Before the Reform, for example, one did not hesitate to say that Christ suffered the punishment due to sins; [but it is only] during the epoque of the Reform [that] one begins to speak of the transfer of our sins to Christ. Thus William of St-Thiery wrote in the Middle Ages, 'transtulit [Christus] in se poenam omnium peccatorum '[([Christ] has transferred to himself the penalty for all sins)]' (Disp. adv. Abelardum, VII; PL 180, 274); Cajetan, on the other hand, affirmed (in 1519): 'Transtulit autem [Deum] peccata nostra in Christum [(But [God] has transferred to Christ our sins)]' (Epist. Pauli. juxtam sensum litt. enarr., in 2 Cor 5:21 (Venetiis, 1531), p. 81)" (69n107).
Sabourin continues: "Such a usage is all the more suspect because these two texts [(2 Cor 5:21 and Gal 3:13)] figure among the principal [texts] cited by the early Reformers in support of their theory of the imputation of sins to Christ and of forensic justification" (69).
It is important to note (as indeed the reference to Cajetan already implies) that Sabourin doesn't charge the Protestants with this exclusively. Indeed, it is of the Comm. in Lev. of Dionysius the Carthusian (Denys le Chartreux, Denys van Leeuwen, Denys Ryckel, d. 1471) that Sabourin, speaking of an "equivocal honor," says, "For the first time in one and the same figure and in [one and the] same context, Christ is represented as a scapegoat marching to Calvary laden with the sins of men" (65). Moreover, Sabourin goes on to implicate in this, in addition to Cajetan, other Catholics of the Reformation period and after as well (69 ff.), including those who have interpreted the gesture of the imposition of hands associated with the Hanc igitur ("Spreading his hands over the oblation he says: Therefore, Lord, we pray: graciously accept this oblation of our service," etc.) as an imposition of sins (75 ff.).
Nonetheless, it is the theory of (mere) imputation that takes it on the chin admittedly. Indeed, Sabourin goes further than this one quotation would by itself necessarily imply, questioning "the [very] possibility of making use of this figure [of the scapegoat] in relation to the redemptive act of our Savior" (45, and in other words elsewhere).
"It goes without saying that our remarks on the new tendencies, revealed at the time of the Reform, are in no way directed against the satisfactio vicaria as understood by a healthy catholic theology" (70n108).