Looking for a (small) safe school

For various reasons we feel compelled to change our 4 year old daughter's school.  She is our oldest, perhaps our expectations are too high.  We expect that she will be at a very minimum physically safe at school, and preferably emotionally safe too.  No, we are not the type of parents that try to protect our child from every bump or bruise.  But weeks in hospital (our experience in France last year) or being strangled to point of losing breath (here) are unacceptable to us.  In both cases no adult intervened or even noticed there was a problem.  This is what causes us more concern than anything else.

Do schools exist where we can be confident that her physical safety is assured?

We've visited a Montessori.  Does anyone have an opinion on Montessori Kids in Lasne?

What about St Johns in Waterloo?

Les Bruyères in Louvain la Neuve?

We're in Rixensart.  Open to suggestions, tho not interested in Le Verseau nor the Waldorf school.  Willing to drive up to 20 minutes in any direction for the right environment.

Thanks for reading.