Erica Milano has very helpfully checked the DAR file for us, and provided the following feedback to me via private message:
In the DAR database the 1st application proving Elihu Johnson as a patriot was from 1907 & 1937 which the proven child was Oran. (There were no supporting documents with these applications). The DAR application (from 1991) that proved Elihu Johnson (child) and sp Alice Bump (which on the DAR application list Alice Bump as his 2nd marriage). The document tying to Harriet Johnson & Charles Caldwell is using a bible record listing Charles & Harriet’s marriage and then ties Harriet’ to parent referencing Conn Barbour Collection, reel 43. (I do not see this image in the documentation it is just listed in the supporting lineage reference) Interesting enough in the supporting documents of this application, there is a letter from the Tolland Genealogical Library referencing Elihu Johnson as the (patriot) - child Elihu and Alice Bump which also list their 8 children. The letter also states that Harriet married Lewis Bunce in 1827.
The reference to Conn Barbour Collection reel 3 to be a citation to the Barbour Collection index of Connecticut Vital Records for Tolland County, which includes several entries which cite to Volume 3, p. 18 of the original vital records. They include two entries for Harriet Johnson:
SO - there does not appear to be any clear evidence resolving the question in the DAR file. Given the strong feelings on both sides of the argument among WikiTree members who have an interest in this family, I think this is probably a situation where the WikiTree guidance on "Uncertain Parents" applies, since it seems possible at this point that either Harriet Bunce or Harriet Caldwell could possibly be the Harriet who was the daughter of Elihu Johnson and Alice Bump.