CL90 would not protect the capacitors from being over voltage as a result of using the T-SSR01, if that is indeed what happened. Weber copper cap should be fine, going forward.
In order to reduce time and money spent needlessly, it would be a good idea to check the internal voltages first, if possible.
As far as Triode USA goes, they haven't answered any of my calls or e-mails in the past two or three weeks. Another problem is parts availability for that cap board. I've recently noticed on Mouser that a lot of Panasonic electrolytics, including at least one that this cap board uses, are now obsolete. There might be some remaining stock left for what you need. If not, you'll have to look to substitute parts, which can get kind of complicated. Does your chassis have the cutout for the traditional placement of the quad section capacitor? If so, this would be a lot easier. If not, you'd have to delve into that cap board or other possible replacement cap boards. Not sure what to tell you about your PayPal limitation.
Maybe someone else has some ideas on what else you might check before diving into this imbroglio I just described.