Now that they have been stopped from doing further damage, they're upset. Never mind that they essentially destroyed the ability to make money from income property in the area, which depends on the water to which THEY (the owners) are entitled. These people are being run roughshod over by Tombstone. Tombstone has a huge water tank that is damaged, and has lost 300,000 gallons of water, and Tombstone refuses to repair it.
The water rights granted to the patentees were granted by federal law. I would be shocked if Tombstone contested the grant of water rights at the time, and absent any assertion of water rights at the time, they are forever barred. Yes, they have letters (informal), and yes, they have a putative right to the water they had