Being so close to the holidays, some people may not be checking in here as regularly, so may not answer. It's nothing personal. Hopefully I explained the math well enough that you can recheck my numbers for accuracy. I'm pretty sure I got it right this time. 
If any part of my explanation isn't clear, let me know and I will try to clarify for you.
Yes, I do this all the time for pills and capsules that are not the correct dosage, and most of the time they are not. I buy the highest doses I can find and divide them into correct doses as it's usually more cost effective, and the bottle lasts longer. For example I usually get 500 mg amoxicillin rather than the 250 mg because it lasts twice as long. I have done amoxicillin, cephalexin, clindamycin, SMZ-TMP, metronidazole, etc all mixed in coconut oil. It works very well for me and allows me to make all the doses ahead of time for the length of the treatment period, which uncomplicates my life just a little. I have also, on occasion given much higher doses than you are giving and have had no issues. Most of the medications are tolerated well, sometimes the sulfa can upset digestion if the dose is too high, then I back off the dose some and give probiotics. I don't have access to a vet that will treat birds so I use Plumbs and other information I have gathered over the years from sources that I trust, including some here. From what I've seen, the people that have offered advice to you here are generally some of the best on this forum, so no worries there.
Since she has abdominal bloat, and the Lily of the Desert helped, then it sounds like ascites, which is a symptom of something else. She has some kind of reproductive problem, and it probably won't be cured. It's often not known for sure until they pass and a necropsy is done. The causes are various, but the bloat is most likely fluid from her liver leaking into the abdominal cavity. It could be infection, a cancer, internal laying, or organ failure which can accompany those. Treatments can buy them some time sometimes, but usually are not a cure. So the goal is to keep her comfortable as long as you can, rather than hope for a cure. Sadly, it's very common in laying hens over the age of 2. Even with the very best of veterinary care there are some things that just can't be treated successfully or cured.
If any part of my explanation isn't clear, let me know and I will try to clarify for you.
Yes, I do this all the time for pills and capsules that are not the correct dosage, and most of the time they are not. I buy the highest doses I can find and divide them into correct doses as it's usually more cost effective, and the bottle lasts longer. For example I usually get 500 mg amoxicillin rather than the 250 mg because it lasts twice as long. I have done amoxicillin, cephalexin, clindamycin, SMZ-TMP, metronidazole, etc all mixed in coconut oil. It works very well for me and allows me to make all the doses ahead of time for the length of the treatment period, which uncomplicates my life just a little. I have also, on occasion given much higher doses than you are giving and have had no issues. Most of the medications are tolerated well, sometimes the sulfa can upset digestion if the dose is too high, then I back off the dose some and give probiotics. I don't have access to a vet that will treat birds so I use Plumbs and other information I have gathered over the years from sources that I trust, including some here. From what I've seen, the people that have offered advice to you here are generally some of the best on this forum, so no worries there.
Since she has abdominal bloat, and the Lily of the Desert helped, then it sounds like ascites, which is a symptom of something else. She has some kind of reproductive problem, and it probably won't be cured. It's often not known for sure until they pass and a necropsy is done. The causes are various, but the bloat is most likely fluid from her liver leaking into the abdominal cavity. It could be infection, a cancer, internal laying, or organ failure which can accompany those. Treatments can buy them some time sometimes, but usually are not a cure. So the goal is to keep her comfortable as long as you can, rather than hope for a cure. Sadly, it's very common in laying hens over the age of 2. Even with the very best of veterinary care there are some things that just can't be treated successfully or cured.
