set up a programme

[suprunp]

But astoundingly, the fearsome invaders who, like most warlike races were only on the rampage because they couldn’t cope with things at home, were stunned by Versenwald’s extraordinary breakthroughs, joined in the celebrations and were instantly prevailed upon to sign a wide-ranging series of trading agreements and set up a programme of cultural exchanges.
(The Ultimate Hitchhiker's Guide to the Galaxy; Douglas Adams)

Is it possible to read the part in bold in two ways?

1) [they] were instantly prevailed upon to sign a wide-ranging series of trading agreements and
[they] set up a programme of cultural exchanges.

2) [they] were instantly prevailed upon to
sign a wide-ranging series of trading agreements and
[they were prevailed upon to] set up a programme of cultural exchanges.

Or is the part in bold should read "were instantly prevailed upon to sign a wide-ranging series of trading agreements and to set up a programme of cultural exchanges." to be able to view it as 2)?

Thanks.

[5jj]

Be wary of trying to analyse Adams's language too closely. He often played with words for humorous effect, though not here.

But astoundingly, the fearsome invaders who, like most warlike races were only on the rampage because they couldn’t cope with things at home, were stunned by Versenwald’s extraordinary breakthroughs, joined in the celebrations and were instantly prevailed upon to sign a wide-ranging series of trading agreements and set up a programme of cultural exchanges.

Is it possible to read the part in bold in two ways?

1) [they] were instantly prevailed upon to sign a wide-ranging series of trading agreements and [they] set up a programme of cultural exchanges.
That is possible, though if this were the intended meaning I would expect to see a comma after 'agreements' and 'they before 'set up'.

2) [they] were instantly prevailed upon to sign a wide-ranging series of trading agreements and [they were prevailed upon to] set up a programme of cultural exchanges.
That's the way I read it.

Or is should the part in bold should read "were instantly prevailed upon to sign a wide-ranging series of trading agreements and to set up a programme of cultural exchanges." to be able to view it as 2)?That makes it clearer, but it's possible without 'to'