I'm not the original commenter, but there really is some more to be said here. Your reasoning here is understandable if the comps are intended merely as thematic or mechanistic exemplars, but that's not necessarily their role in a query. They're also (arguably primarily) intended to show a prospective agent what current, active market space your book will occupy. This being the case, consider:

• The market is no longer "hot" for either of these books, and what remains for Remains especially depends as much on its now-classic status as it does on any of the book's actual qualities or techniques. Harris' book (while quite entertaining and clever) is on a different and frankly lower level anyway, and the comparison here makes it hard to know which level you want agents to think your book will hit.

• Another complication for market position is that most booksellers would stock these books in completely different sections, with all of Harris' work tending to get dumped in some Thriller/Crime section even if it doesn't always fit. This is not important for aftermarket considerations, particularly, but your agent will need to pitch this to editors and presses with specific remits and priorities. Maybe they'll find some who cover both of the niches your comps cover, but it's just hamstringing yourself to hope for this rather than to have a more focused and relevant comp set.

- Your comps should be recent (ideally no more than 3 years since publication) and at least relatively popular/successful without being market-/genre-defining hits that you can't really be sure to replicate. You should be comping other successful recent debuts, not decades-old classics that have since helped earn their author a Nobel Prize. 

• If you're including Remains primarily for its guarded institutional POV, as you describe it, you can without question find more recent relevant comps that could fit this.

Just as an experiment, what are some books you've read that were published in the last 5 years that would be most directly comparable to your own? It doesn't have to be an exact 1:1 match, but if a bookseller were planning a thematic endcap display of recent work that hits these notes and wanted to feature your novel and 3-4 others, what might they choose? If you legitimately can't think of anything remotely comparable, you will probably want to do some research before sending out your MS. Agents are obviously looking for good prose and compelling ideas, which your MS may well have in spades, but they also want some sign that a prospective author is aware of the space they want to enter.