Is there a way to verify a pigs age? Do any shows use this? (If there is). Feel like breeder is not giving me correct farrowing date

yes, but not sure the procedure and expense. Cell Telomers can be measured to determine accurate age.

The NSR covered this topic spring (March) magazine. If age was verified on pigs the showing will look massively different as the 10-12 month old pigs that are shown as 6-7 month old pigs would be outed. Way, way past time for this.

Quote from NSR CEO Clay Zwilling "When recording the proper date of birth seems to be the exception, not the rule, we should all be alarmed and concerned"

Yes, effing yes.