。
Do you think she can keep the staff together?
Literal
She [topic-は] staff [object-を] put-together can-go-on [quotative-と] think [question-か]?
まとめていける chains まとめる ('to gather / consolidate / put together') with ~ていく ('keep doing / continue going forward') in its potential form ~ていける ('can keep doing'). The combination expresses sustained capability — not just 'can manage them once' but 'can keep managing them going forward'. ~ていく specifically points outward/forward in time from the speaker's vantage, the directional opposite of ~てくる ('come up to now'). The polite ~と思いますか asks the listener for their judgment.