Just regarding the tardigrade - the other characters are trivial
It may be ridiculous, but it's hardly trivial - it is the basis of his case that Discovery must have copied from him specifically. Without his 'other similarities', you are left with the case being that nobody could have independently come up with a space faring tardigrade which has a whiff of desperation about it as a claim, given the coverage of tardigrades surviving in space and the long scifi history of 'creature, but in spaaaaaace' which Discovery even went back to with the space whale.
None of the rationalizations advanced here so far for the plausibility of the "coincidental" invention have been anything other than funny - certainly not persuasive on the merits
The rationale for it being anything but a coincidence (which isn't really the right word, anyway - the argument isn't that they sprung from nothing into their heads, but that they came to the same idea from similar inspiration) is essentially pointing and going "look, a space tardigrade", especially if one ignores the 'trivial' bits.
Ultimately, as I said earlier, this is why film companies keep memos, initial sketches, minutes from meetings etc. It helps prove how ideas came about.