The solar flair only interrupted communications and tracking it didn't damage the ships.
The 6 ships initially sent to colonize the system disappear suspiciously, and the only transmission that gets back reports complete systems failures. Forcing the UCN to open up the the rights to a contract... and the Helghan corporation just so happens to have an entire fleet of colonization ships almost completed just in time to bid on the contract... admit accusations of massive corruption and bribery.
Now it's true that they weren't the only company bidding, but they were the only company with an almost completed fleet that was
just sitting around.
I'd say it's fairly suspect.
No, I am very well aware of this. but ISA =/= UCN. The UCN seized Vekta by force from the Helghast, correct. But during the 142 years between then and when the Helghasts invaded in KZ1, several non-Helghasts made Vekta their home whether they agreed with how it got in the hands of the UCN or not. The ISA are an army separate from the UCN tasks solely with defending those people. So yes, I stand by my point.
The Helghasts invade Vekta in Killzone 1 to reclaim it from the UCN, only instead of fighting the UCN they fight the civilians militia who had nothing to do with taking it from them in the first place. And then they retaliate because they feel threatened.
Lets not forget Visari's plan here:
Utilize deep-cover agent ISA General Stuart Adams to neutralize the orbital defense platforms.
Utilize deep-cover agent ISA General Dwight Stratson to gain access to intelligence and lure the ISA troops out of the cities.
Mount an invasion of Vekta whilst the orbital defense platforms are down, under the command of General Joseph Lente.
Reactivate the defense platforms in time to defend Vekta against the inevitable support fleet sent by the UCA.
Declare the system to be under Helghast control and sue for peace with the UCN whilst the UCA is still reeling from the loss of its fleet.
Use the resources of Helghan and Vekta, as well as technology captured from the wrecked UCA Navy fleet, to build a Helghast fleet capable of defending the system from the UCA Navy.
Begin charging trade tariffs for passage through Helghast space to Earth again.
Blockade the Earth and strangle the UCN into submission.
Capture the UCN Navy shipyards and orbital defenses. Leave Earth's population to starve to death. Build an enormous fleet and establish Helghast hegemony over all colonies.