Beg to differ. There are instances I know of where one side has fought against an annulment.
Consent does not enter into the nullity process.
What you are describing is someone who gave evidence of validity or presented an argument for validity. That is not the same as “consent.”
If the evidence pointed to validity, the decree of nullity would not be granted. If the evidence pointed to invalidity, the decree would be granted regardless of the other person’s “consent.” Certainly this person also retains the right to appeal.
It’s far from routinely granted to anyone who asks.
No one has put forth such an assertion.
Factual statements have been made: nullity petitions doe not require “consent” of both parties. They require notification of both parties. Both parties can respond and give evidence.
Also, a nullity case can be in one of several jurisdictions. Your statement that this person must contact his “ex’s” pastor is not accurate:
Can. 1673 In cases concerning the nullity of marriage which are not reserved to the Apostolic See, the following are competent:
1/ the tribunal of the place in which the marriage was celebrated;
2/ the tribunal of the place in which the respondent has a domicile or quasi-domicile;
3/ the tribunal of the place in which the petitioner has a domicile, provided that both parties live in the territory of the same conference of bishops and the judicial vicar of the domicile of the respondent gives consent after he has heard the respondent;
4/ the tribunal of the place in which in fact most of the proofs must be collected, provided that consent is given by the judicial vicar of the domicile of the respondent, who is first to ask if the respondent has any exception to make.