https://www.ncbi.nlm.nih.gov/nuccore/MN908947.3
I do believe the circumstantial evidence suggests that this virus might be man made likely in the Wuhan institute of virology but... you are incorrect when you suggest the multiple repeating a's in the viruses genome are incompatible with nature. Such repeats are known to exist in viruses. This one in particular is known to exist in the HIV virus.
Long Terminal Repeats
https://en.wikipedia.org/wiki/Long_terminal_repeat
...
HIV-1
Poly A plays roles both in dimerization and genome packaging since it is necessary for cleavage and polyadenylation. It has been reported that sequences upstream (U3 region) and downstream (U5 region) are needed in order to make the cleavage process efficient.[9]