You are certainly correct. I agree completely. The key to resolving the disagreement is to quite slamming each other and for Mr Van Curen to provide documents which support his alternate theory that Maria Van Sicklen (not Maria Van Siclen) married Luther Eastling.
Mr Gusman challenged the Eastling connection with the Van Sicklen genealogy and submitted documents that appear to support his challenge.
It is not unreasonable for us to expect Mr. Van Curen to provide conclusive evidence proving that his version of the marriage of Maria Van Sicklen (not Maria Van Siclen) to Luther created a legitimate connection with the Van Sicklen ancestry.
Altering data in Mr. Gusman's documents, as Mr. Van Curen has done, proves nothing. Mr. Van Curen must submit original evidence as proof for the marriage of Maria Van Sicklen to Luther.