as far as I have been able to determine no detail is transmitted about the contributions except when form 8283 is needed. if you look at schedule A all cash contributions go on line 11. There isn't room to detail cash contributions even if filed on paper. if the IRS wanted details there would likely be a supplemental schedule to detail them. could you be audited if cash contributions are large - yes - but it would likely be due to the amount being out-of-whack with the income reported. when I was active in preparing returns and there was no electronic filing clients often asked that I show the details on schedule A for the largest (there was a lot more room on Schedule A back then). once e-filing started and I told them the computers at the IRS couldn't read the names and that less time meant less fees, clients changed their minds.
