Despite some historical cases to the contrary, it remains established that in the Church the only one who can celebrate the Sacrament of Holy Orders, in all three of its degrees, is the bishop, with no exceptions. (Mauro Gagliardi, Truth is a Synthesis: Catholic Dogmatic Theology [Steubenville, Ohio: Emmaus Academic, 2020], 710-11)
Note the following:
There were a few cases in which the Apostolic See authorized an abbot to ordain subdeacons, deacons, and priests for his own monastery. The question is to this day not completely clear: if such abbots were ordained bishops, there would be no dogmatic issue; it appears, however, that they were only presbyters. We can recall the following cases: Boniface IX, with the bull Sacrae Religionis (1400), authorized the abbot of Saint Osyth (near London) to carry out such ordinations, though it must be said that the permission was withdrawn very early, with the bull Apostolicae Sedis (1403). Martin V, with Gerentes ad Vos (1427), authorized the abbot of Altzelle in Saxony for five years. Innocent VIII, with Exposcit Tuae Dovotionis (1489), granted the abbot of Citeaux permission to ordain deacons and subdeacons. There has been no shortage of historians who considered these documents "surreptitious bulls," that is, indeed without the knowledge of the peoples. Beyond this, what counts most is that these cases were very few and that these privileges were more or less quickly withdrawn. This is an indication of the fact that the Church—except for a few oversights—does not contemplate in her practice the possibility that a presbyter may carry out sacramental Ordinations, even if (as for the abbots) he possesses the juridical power of an Ordinary and bears episcopal insignia. (Ibid., 710-11 n. 89)
Note: in Catholic sacramental theology, priests cannot validly ordain priests; not just because it is not licit, but it does not bestow the sacrament to the candidate; only a bishop can create new priests (and bishops).
