No, you cannot do that. You can only take an exclusion, partial or full, once in a 2-year period. There must be a full 2 years between the closing dates of the two sales. It's determined by the length of time, not calendar years.
If you already took a partial exclusion on the first sale, you could file an amended return for that year to remove the exclusion. That would mean, of course, that you would have to pay additional tax for that year. Then you could take the exclusion on the second sale.
It's not clear what you sold when, and how long you lived in each home. You wrote "First main home sold was only inhabited for a year," and also "original main home before unforeseen event lived in 3 out of 5 year prior to sale." Are "first main home" and "original main home" the same home or two different homes? If you have more questions, please clarify the details of the two sales. But in any case you cannot take an exclusion more than once in any 2-year period.
