Gruff Garrett The Old Lawdog - No Way Out. Gruff Garrett Series, #6

Claudio Henderson and his gang of outlaws have pinned down Gruff Garrett and his unusual trail partners, Paolo Dixon and Alisa Pemberton. Dixon was supposed to be Garrett's prisoner, whom he was escorting back to a secure jail, and Alisa was a lady in waiting Garrett had saved along the way from her unscrupulous and abusive employers. The three of them were ambushed by Dixon's gang who tracked him down, to make him pay for double-crossing them, and running off with the gang's money.
Dixon had always warned Garrett that his gang was coming for him, but he ignored the old outlaw. When they arrived, they caught Garrett and his companions off-guard, taking Dixon and ravaging Alisa. Garrett and Alisa managed to track down the gang and rescue Dixon. The gang came after them, and pinned them down in a tall cave.