This isn't true. A mixed marriage can infact be valid.

Mixed marriages are only valid if... the marriage is done by a priest, through the Catholic Faith, with the Church granting an exception. 

The OP said the first marriage was by a protestant service.  That's probably why the novus ordo priest said it was invalid.  A catholic cannot validly marry in a protestant service.  And I would agree.

In regards to the "2nd" marriage in the novus ordo...If both you and your spouse were baptized, then it's valid.  Novus ordo marriages are valid because the sacrament mainly depends on the 2 people, not on the priest (even if he's an invalid priest).  You are still married "in the Church" (that was your intention).

Please provide all the details on the first marriage -- persons, baptism status, pastor details, etc

Baptized Ukrainian catholic + unbaptized

Marriage occurred in a Protestant church

NO tribunal offered two options
- Lack of Form
- Petrine privilege

Tribunal recommended Petrine route as being a more expeditious solution.  This was granted

The marriage to the heathen Ukie is a valid, non-sacramental marriage. Were the Ukie subsequently baptised, the marriage would become sacramental.
Non-sacramental marriages can be dissolved in favour of the Faith (Petrine Privilege, Pauline Privilege), but sacramental marriages can only dissolved by the death of one or both spouses.

Understanding marriage validity can be complicated and confusing to those untrained in canon law, whether Corpus or 17 Code or 83 Code. For example, the marriage between two baptised Protestants would be presumed valid and invalidity would need to be proved. Or,  Catholics are bound to canonical form for validity. Or, certain defects can be sanated (cleansed) at the root validating a marriage ex post facto. Or, a civil  marriage or one attempted before a non-Catholic minister can be validated by convalidation before a Catholic minister with delegation. Ah ... delegation! For validity, one must contract marriage before a priest or deacon with faculties from the ordinary bishop or with delegation from a parish pastor. Oh ... oh ... and Eastern Catholics must have their marriages conferred by a priest, never a deacon which would likely invalidate the marrige because, whereas in the Latin Church, the spouses marry each other before ecclesiastical witness, in the Eastern Churches the priest (and never a deacon) confers the sacrament on the couple.

I was engaged to a heathen who was previously “married” to a Ukrainian catholic - they were married in a Protestant service

Baptized Ukrainian catholic + unbaptized

Marriage occurred in a Protestant church

NO tribunal offered two options
- Lack of Form
- Petrine privilege

Tribunal recommended Petrine route as being a more expeditious solution.  This was granted

The marriage to the heathen Ukie is a valid, non-sacramental marriage. Were the Ukie subsequently baptised, the marriage would become sacramental.

Non-sacramental marriages can be dissolved in favour of the Faith (Petrine Privilege, Pauline Privilege), but sacramental marriages can only dissolved by the death of one or both spouses.

I think this is the timeline.  The OP is horrible at describing the story:

1.  The Ukrainian catholic MAN + unbaptized WOMAN = valid, non-sacramental marriage.

2.  unbaptized WOMAN meets OP MAN and seeks the pauline privelege.  NO tribunal says yes.

3.  unbaptized WOMAN gets baptized and marries OP baptized MAN in the novus ordo, by (probable) old-rite priest.

I think the original valid, non-sacramental marriage is replaced by the pauline privelege/catholic marriage #2.

Thanks for the commentary…

The question remains:  Is a NO tribunal competent to judge this case?

The most complicated cases to "judge" are annulments, because it involves 2 baptized persons and a "possible" sacramental marriage.  There's nothing trickier than this.

The case of an unbaptized + baptized + protestant minister is a pretty straightforward 'not sacramental' answer.  This is textbook stuff.  Pretty simple.

Looking for some insight on my status.  I have a sede perspective now but in Tradition since at least 1990

I was engaged to a heathen who was previously “married” to a Ukrainian catholic - they were married in a Protestant service

My fiancé petitioned the NO tribunal for relief.  It was decided that the Petrine Privelege was the best route (better than Lack of Form).  This was granted in favor of the husband

My fiancé was baptized (and confirmed by a NO bishop)

We were then “married” by a NO priest (who was likely ordained in the old rite) in the traditional manner

Now I’m divorced from her for two decades

I’ve maintained my vows

AM I A MARRIED MAN ?

I don’t believe the NO structures have authority

Thoughts?

Thanks

m

Yes you are still married.  I'm sorry if that's not the news you wanted. The authority to marry validly comes from the couple themselves (lack of impediments, valid consent).  NO marriages are valid.

Many of us were divorced against our will and must stay single the rest of our lives.  Kinda stinks when you are relatively young.

Agreed, it stinks

But there seems to be a conflict between marriage #1 and marriage #2

I’m trying to resolve that conflict

The question seems to be - IS A NOVUS ORDO TRIBUNAL COMPETENT TO RENDER JUDGEMENT of the conflict ?

Marriage 1 was a natural marriage, not a sacrament.  The Pauline privelege allows the replacement of a NATURAL marriage with a SACRAMENTAL marriage.  Marriage 2 was a SACRAMENTAL marriage.  Marriage 2 takes precedent and is still valid.

It doesn't take a "tribunal" to discern that Marriage 1 was only natural.  This is basic stuff.  The tribunal is right.  Any Trad priest would tell you the same thing.