Both are bumblers to a certain extent, but I'm thinking that Dr. Lorre would be less so than Tom in many ways.
Yes, he has lost to Daffy Duck in an encounter the two of them had, however his loss included that of forcing Daffy to retreat from his house, due to how dangerous it was, and how dangerous he was. In that cartoon, Daffy was hoping to lodge at Lorre's house during the Winter, rather than go South, as all the other ducks tended to do, and because of the danger and madness that Lorre posed and had, Daffy was eventually forced out, not because he couldn't best Lorre if he wanted to, but rather because he didn't want to deal with the danger he was in any more.
That being said, Lorre is a pretty smart and a pretty inventive scientist, as he developed much of the traps and aspects of his house by himself, created a mechanical rabbit android to lure Bugs Bunny into his castle in another short, created a machine that forced Damian Drake to slap himself in the face, and either created or had enough capability to hold Gossamer in his castle for some time before Bugs Bunny arrived in Lorre's first cartoon appearance.
With that being said, I do believe that Lorre could find a way to get rid of the insects, perhaps even more so than Tom, as Lorre aside of his technical intelligence has probably a much more level head than Tom does, and his aura of being unnerving to be around would make even the insects feel creeped out, especially if he goes after them in the same way he did Daffy, to acquire a part of them, which would likely kill them in the process.