Both are Possible

Here's the video. Although the launcher looks familiar, I doubt three engines will work since the central engine won't have enough thrust to reach the target. A boost-back burn is demonstrated.

What is your standard for "too much thrust for landing"? I am not aware of any theoretical upper limit. greater thrust and acceleration make control more difficult, but not impossible.

Theoretically, if thrust increases to infinity, the vertical speed will also go to zero. In a real-engine, there's a certain minimal time for startup+thrust+shutdown. Particularly, if the turbopump is involved. The stage dry mass is the most effective source of landing engine thrust.

In addition, since we're likely to be looking at the launcher to be 100 tons or more The engine will likely require a larger engine than the F-1.

First, F9 can land using 3 out of 10 engines. In that context landing on 1 out of 3 engines does not seem to be too extreme.

If you're looking to posit an infinite thrust engine you might as well posit one with an infinite start up time. Both are possible. None of these conditions are relevant.