Since she had signed the trust amendment naming Meghan as the beneficiary of Damon’s financial assets, she definitely had a financial motive.
Because of Damon’s recent use of deadly nightshade for his Parkinson’s, she had access to deadly nightshade.

Backstory…

She met Damon at the Penham Institute when she started as an intern and he was a technician before skyrocketing to fame and fortune at Biopharm.
Once married, she stopped working after their son, Oliver, was born and at that point, Damon was a director at the institute.
She was also a fitness model when she met Damon, which she then transitioned into CrossFit and later became the owner of several CrossFit locations around London. CF Old Towne is one of them.
Going hand-in-hand with this healthy lifestyle, she soon after started Killer Kombucha.
*She had all of the elements to commit the crime, except the right opportunity to commit it, if she was looking to do so.
Being at the kombucha contest at Harold’s until 18:30 and then to dinner with her family at the Lanesborough by 19:00 doesn’t allow for enough time.
She is the reason Walter “Mickey” Cunningham went missing.
He had confronted her about the email found from Meghan to Damon about the vaccine failure and threatened to expose them.
But that’s for another case!