Under normal circumstances, it would be irresponsible of Krishna to take Lachlan's word at face value and not check on his own. Yet, because of all the interwoven complications of their situation, the most sensible way he could deal with the two of them would be to... simply accept Lachlan's words. If he opened up Lachlan's back, there was no way the wound could go ignored in the next day, and that made no sense when there was no real certainty that anything had been left in there.
Besides, Krishna knew how dedicated Lachlan was to the cause. Krishna had always suspected that he had paid a hefty blood price for it. Not being caught for whatever they had been up to that night would be their priority.
"Finish your tea, then go." Krishna didn't care that Fiona had likely set a bomb off somewhere, she had come to him for help and this was his best advice for her. He straightened from peering at Lachlan's back and went to get a curved needle and silk thread. "Ms. Dunn did a good job with healing you. I'm going to stitch it up and wrap it to keep it close. You're going need to be very careful about who you expose yourself to until the stitches can be removed." He took the needle to the stove and heated the tip up. "You're also going to need to take it easy for a couple of weeks so it doesn't pull apart and bleed down your shirt. That attracts attention."