A good DVM, like a Fluke 87 (industry standard) will have what's called dc blocking caps, one per lead ( internally) when trying to read the AC component..while DC is present... IE: meter switched to read ACV. ( DC will not pass through the capacitors). IF the caps are not present, then what happens is the meter will instead read the DCV. IF caps were not present, and you are on the ACV mode, the meter will read 14.75 vdc etc..... but NOT 32 V.
Your yellow meter appears to be reading 32V. But your red meter appears to be reading minimal ACV.
You may well have a lousy grnd connection somewhere...and when you pull current, you end up with a V drop across the shitty connection. Pull more current, and the Vdrop increases.
Assuming the start motor works good, and the battery is good, it's down to either a fried alternator, or bad grnd(S) or both. I can see perhaps one bad grnd connection, but not multiple bad grnd connections.
You might just want to check some of the grnd connections 1st... before buying a new alternator.
If you do find bad grnd connections, they have to be repaired, and perhaps some permatex dielectric grease on the connection, to keep moisture out.