Reasoning 101: A strike against any war criminal (such is Assad’s status) does not cause to vaporize evidence of affiliation between the Trump campaign and Russia. That’s wishful thinking.
Your argument has the reverse effect of your intention. It suggests that Trump may have used this military situation deliberately to dispel claims of association between the WH and the Kremlin.
That may have been a secondary motivation, but the use of chemical weapons has long been a red line for the US. After the 2013 agreement between Obama and Russia to guarantee Syria’s non-use of such weapons, the only response was military punishment. Obama would have done the same. Syria cannot violate an agreement like that and not suffer some consequences.
Further, Trump knows that attacking Syria reshapes his domestic and global image and functions as a distraction from numerous other issues plaguing him. This was a perfect opportunity for him to look like a world leader and not an incompetent schmuck.