Can beginners snowboard in Switzerland in October? Is it worth going?

If summer happens to be dry just the fact that there is a glacier won't make it snow. Last year summer was very wet, so there was powder in July/August. It doesn't mean there will be powder next July. Dry spells are not uncommon in Switzerland and they can last for extended periods too.

So ..they wanted a suggestion as to where to ski whilst in Italy...there might be a good chance of that there and as they are going in October they can look if there is any there before they go

I live close and can guarantee you that October is far too early

However, skiing is possible all year round on the glacier (for example Glacier 3000, which is as the name says at 3000 altitude) or take other resorts with a glacier. Verbier will not be open for skiing at all around that time, though it has high altitudes.

Note: this year the season started relatively late in december, the year before it started earlier in november (but we had bad conditions soon after). I.e. October is really a big gamble

You might have better luck if you stay in Italy, go to the Sud-Tirol area in Dolomiti depending on where you will be staying this is only a few hours drive from Milan