I meant 'collaborate' as in having talks or meetings, paying a 'tax', playing by their rules... nothing that leaves much of a record.
'Ties with militant groups' is vague enough so many people will read 'on the terrorists' payroll'. And on time some 'proof' like phone calls, pictures in the same place with a 'militant group' member, or handing them some material aid, going to the same mosquee...
The thing is unless they're able to articulate more concrete accusations I wouldn't even ask for proof, proof of what? I mean I have a bunch of cousins I barely met when I was a child, and no clue what they've been up to these ~30 years... I might have some 'ties' to 'militant groups' too, who knows?