Trouble with math? Your "group" consists of one dissimilar sale. One is not a group. You can cheat and use your fingers if needed.
What's a better comp, a 100% identical sale two years back or a very dissimilar sale now? The answer is A, the time adjustment is one of the most easiest and reliable to calculate. The best comps would look like B, however we don't have any in this case, only the subject's own prior sale. The comp on Walnut looks very little like B. And since you are only interested in rehashing this: the reason I didn't bother to look is that I was never asked to appraise the property. Meanwhile you botched your comp search so badly I didn't know whether to laugh or cry. Partly due to lazy methodology and partly due to lack of geographic competency (which you would be quick to crucify anyone else for).
Carnivore's marketing time scenario is totally flipped against reality, and it is the reason the Garfield lot listing was withdrawn, and why you can't show me any examples where the lots went to separate buyers but I can show you 100 examples where they went to the same buyer. Because although the typical seller may be interested in maximizing profit among other things, the typical buyer is neither interested in developing a vacant lot, nor living next door to a construction site.
And yes, as J Grant pointed out the "over your head" comment says it all. Coming from someone who can't tell the simple difference between two questions, "what are the two parcels worth if sold together" and "what are the two parcels worth if sold separately".
Regarding a duplex/triplex tell me this. You have an illegal triplex zoned duplex, does this mean you comp it out with only duplexes because that's the HBU? No, the best comps are going to be other illegal triplexes (given that the jurisdiction allows them to transfer, which most do in CA). And don't try to tell me that no lender will take it, because you are clearly much more interested in theoretical practice than what the lender wants.