Dollys seem to always have been rather dangerous landings spots,
another squirrel: in this case slipped off the platform and caught the platform with the right skid's rear snowskid:
https://www.youtube.com/watch?v=Vxi9iKOW04w
ASN Aircraft incident 18-JUN-2008 Aérospatiale AS 350B2 Ecureuil HB-XVB
Then again, in that Swiss final accident report
http://www.sust.admin.ch/pdfs/AV-berichte//2110.pdf on p.7
that dolly doesn't look inappropiately small, to me layman.
But that pilot clearly operated out of his comfort zone (as can be gleed from the fact that radio communication
with the tower changed from official english to local schwiezr-dütsch when he hesitantly acknowledged the request to land on the pad)
Btw. rather decisive ruling by swiss authority followed:
- starting with Oct. 15th 2008 it is illegal for airfield operators to offer publicly usable dollys
- effective same date said airfield operators (!) must ascertain that privately owner dollys be used only by pilots who can prove sufficient experience and training with helicopter platforms, by having been issued a respective permit by the swiss aviation authrority