FWIW, multi-channel hobby chargers can't be used simultaneously on the same battery/cell unless it is specifically documented it can do that. It will typically be listed as "synchronous mode."
The linked HTRC one definitely won't (I have one), and the HOTA probably won't either.
I have an iCharger 4010B Duo that does have a synchronous mode. Can use both channels to charge at up to 70A/1400W with other limitations, but it needs to be fed from DC with the input current limited to 50A.