Under par -
I've been a Landman for more than 30 years and have run into this sort of thing many, many times.
The least expensive way for you or your wife to discover what you own is to simply let the Landmen for the various companies provide you with the information as they discover the interests over time. Most will even be happy to provide you with copies of their maps, title notes, etc., regarding your interests for your files.
This may take years, but it's free.
At some point, the Landmen with the companies you have been dealing with will be preparing Affidiavits of Marital and Family History, Affidavits of Heirship, or something of the like on your wife's family to file of record, thus "curing" the title defects to your interests.
You will probably know when they get around to this, because it will require interviews with various family members and close family friends. As a matter of fact, you or someone else close to the family will probably be asked to be the Affiant in the Affidavits.
Ask the Landmen to provide you with either duplicate originals of the affidavits or certified copies of them after they have been filed of record.
You can file those duplicate originals or certified copies of record in any of the 254 Counties in Texas you think you might own interests in and your title will be clear - at least down to the present generation.
If the Landmen have not prepared any or aren't going to (which I've never heard of, but I guess it could happen), then you might consider preparing one yourself.
Even if you don't have all of your family's history (the Landmen may be able to help with that), you can at least prepare an Affidavit that your wife is one of the heirs of her great grandparents and grandparents.
Be sure to include your contact information.
If you will send me the names of the great grandparents and grand parents and parents, I can check the general area around the two counties you know about and see if their names show up in any producing wells' "suspense" accounts.
You should also check the records of the Texas Unclaimed Properties website - the State may be holding funds under their names: https://txcpa.cpa.state.tx.us/up/Search.jsp
Every state has an Unclaimed Properties office of some sort, by the way, but be forwarned: They're addictive.
Hope this helps -
Charles
Charles Emery Tooke III
Certified Professional Landman
Fort Worth, Texas