[Abhiditya Sharma]

I think second option is good to sound as having a good spec is better than invest in old one

One more suggestion that rather than sony 7r v go with a1 or a9iii they are better option

And for lens go with 400-800 because with tele converter on 100-400 it also double the f no like (5.6 x 2 ) and it also make image softer

So at last consider my suggestion

Bonus tip if possible search for canon r 6ii or r5ii and lens 100-400 or 200-800 option

[Abhiditya Sharma]

Hello I have one suggestion that go and try with other 7m3 camera too

As we don’t know that problem is with your gear or lighting issue

Put both camera in same setting,same lightning and same lens

It will clear that is your gear faulty or not