If you were an SSPX bishop and a defecting NO priest wanted conditional ordination, you could not automatically do that without risking committing a serious mortal sin, that of sacrilege - for both you and the NO priest.
You would need to first investigate his prior ordination to see if indeed he has to be conditionally ordained.
Well, I'd argue that the reason that "conditional" ordination exists is to handle the exact situation we're in. The only investigation that is needed is to find out
1) Were the bishops who performed the ordination consecrated bishops from the old rite?
1a) If made bishops in the old rite, then they were valid bishops. Move on to question 2.
1b) If made bishops from new rite, then they were "probably" not valid bishops. Conditional ordination should happen.
2) A valid bishop performed the ordination. What ordination rite was used for the priest, old or new?
2a) If old ordination rite was used, then a valid priest. Investigation over.2b) If new ordination rite was used, then "probably" not a valid priest. Conditional ordination should happen.
This is the only investigation that could happen anyway. What's the sspx going to do, call in witnesses and ask them about watching the ceremony and if they remember certain latin phrases?
until the Church comes out and says the NO Orders are null and void after the manner of Pope Leo XIII, as he did with the Anglicans, their prior Ordinations must be investigated in an effort to determine whether or not they may be conditionally ordained.
If the Church came out tomorrow and said the new rite was absolutely invalid, then all the novus ordo "priests" would be ORDAINED, not CONDITIONALLY ordained. Conditional ordination is for cases when you don't know or are unsure about all the details. The anglican rite is absolutely invalid, so they were never bishops/priests to begin with.