This is a Solid State Relay.
Not a relay with a coil.
The site shows a sketch about how this is done: it is nothing more than an LED driving a switch.
You are making calculations as if you are driving some Ohmic load, but this is not true.
The SSR requires >2.4 V.
You can limit the current to be some 15 mA per SSR, i'd be surprised if that would not be OK.
In case you already have those relays, you can simply switch them using a 5 volt source (they will not be destroyed as protection is built in), and measure the current.
I would do that myself, but i don't know whether you are able to do that.
You can also switch both SSR in series, and have them "both use the same current".
Downside of that is that 5 volt is a bit too close to the minimum of 4.8 volts required, and if either one of your relays' LED fails, the other one will also fail.