Hi Lucus,
Dentith's names are all listed on the title page of his dissertation (Q112201029). Some of them don't exist as given names in Wikidata yet, but I don't have the energy to create them for this special case. You could however reinstate the deleted ones using the thesis as a ref if you liked.
I’ve added that thesis as a reference to the first given name (P735) statement; I feel no obligation to reinstate “given names” that are in fact items for unrelated non-name concepts.
(Given that the thesis is from 2012, that their website and academic identifiers only identify them as “M R. X.”, and that they are nonbinary according to a sadly unreferenced statement on their item, I was also wondering if they still go by all those names or if they might have left them behind, but this archived tweet would seem to confirm that they still used those names last year, at a time when they already had they/them pronouns in their bio.)