How reliable are holcombe's letters

https://www.dropbox.com/s/6invajbk0zzo4jm/Letters%20Edited%20for%20Distribution%20(Mary%20Lou%20Montagna).doc?dl=0

i question the accuracy of page 153 since miguel's will said that he only had one daughter named isabel. so it's unlikely the jose cid is miguel's son. also how did holcombe verify that the pedro cid who married maria carrillo is a son of hernan gonzales and maria cid