I don’t have an official answer for you, but the receptacle on the US power supply is NEMA 5-15R, which means 120V @ 15A, but the fuse is only rated at 10A (Elite Masso Power Supply Fuse Schematics FAQ) as you indicated. I’ve seen this a lot where the receptacles are only rated for 10A even though they use a 15A standard. In fact it’s actually quite difficult to find a reasonably priced receptacle that is actually rated at 15A and even more difficult to find one at 20A.
Based on a different thread, it looks like the vacuum is solid state with an MOV across the supply line. I can’t see the part number for the FET (or TRIAC) but I’m guessing it’s not rated for 20A based on the size and the lack of a heat sink other than the copper on the PCB and the via stitching.
If you are adventurous, given the power supply has a fuse, you could try it out and if you fry the fuse simply replace it?
Hope this helps.
-Tom