Can my friend extend their tourist visa at Chaeng Watthana Office before it expires?

I am doubtful your Malaysian friend has ANY visa here, and more likely they showed up and were stamped in FREE for 60 days on the visa exempt entry program <- that is not a tourist visa, it's not a visa at all, just a free entry stamp of 60 days

In Bangkok you can apply for an extension when you have 45 days or less left on the current stamp right down until the last day the stamp is good for

Now if they did show up on a real tourist visa that they bought from the thai consulate before they came here they would go to Chaengwattana to get the extension

BUT

If they just showed up and got in on a 60 day free entry stamp (visa exempt) they would go to the alternate immigration office located in IT Square Laksi Plaza.

Keep in mind Immigration offices country-wide have been closed for the last FIVE days so it's going to be a mad house at any office today and tomorrow.

They either get the 30 day extension on or before their current stamp runs out

OR

they use a service and bounce out/back at a land border to get a new 60 day entry stamp